THD UniValve Head

Nice set of features for a simple amp. Not cheap, but well built and unique in what it offers. I use it with a preamp and effects unit. Wish it had an effects loop. Plenty of power.

Use it with a Tele (5-way switching), Gibson LP double cutaway with P-90s, and Tele HH with Duncan SH2n and SH4 pickups.
Overall sound stock is not very good - excess of treble and some nasty breakup scratchy sounds when you drive it hard. In the clean settings its OK, but lacks full sound. I eventually made serious mods to the circuit.
Check out my mod at http://sites.google.com/site/stringsandfrets/Home
The result is absolutely stunning - the amp performs beautifully. If you have a Univalve and you're not happy - try the mod - its so worth your time.

Seems reliable - well built in many respects. There were some issues with the Hot Plate control getting dirty and noisy, but I've cleaned it once (per THD service bulletin) and it's been fine since. I've had the amp for over 3 years.

Reasonable. I wish THD were more open about the circuit schematics. I have searched for them and finally just dissected it myself. They could have saved me a lot of time.

Now that the amp is modified, I would not trade it for anything I've ever heard or played through. Again, see my pages for info on the mod
http://sites.google.com/site/stringsandfrets/Home

Its pricey new, but there are a number for sale used now that you can get for less. It's worth picking one up if you do the mods.

Unsure of year, but serial is 1352. I have owned my Univalve for 12 months now and am ready to write a report.

I play all types of guitar music and have owned a raft of lesser amps - Marshalls, Fenders, Roland, TubeWorks - nothing comes close to this class A single-ended beauty. I consider it a serious musicians tool, not something that will give the instant gratification many manufacturers need to push.

The controls are adequate for the purpose - but you have to spend time learning the amp and to get the best out of your guitar and speaker combination, try different valve combinations - no other valve amp has this flexibility.

I use two guitars:
Electric is a PRS Custom 24 with a Dragon in the neck position and HFS in the bridge (I used to own five guitars - Gibson, Fender, Ibanez however after owning the PRS for 2 months I discovered I only need one electric guitar)

Takamine - sorry forget the model - 6 string acoustic with piezo pickup.

I have several effects but generally only use a MI Audio Neo Fuzz (buy one!).

I use high quality Mogami cables with Neutrik connectors.

This amp makes no noise - even fully cranked....

Sound depends on the type of tubes you choose to use, also the speaker cabinet.

Some combinations I like:
Want it clean - ECC81's for INPUT and DRIVER, 5881/6L6CG for POWER
Want it dirtier - ECC81's for INPUT and DRIVER, EL34/EL84 for POWER
Want it woody - 12AX7 for INPUT, ECC81 for DRIVER, 5881 for POWER
Want it woody/dirt - same as above but sub EL34 for power
Want it Yum - 5751 for INPUT, ECC81 for DRIVER, 6L6CG fo POWER

I don't enjoy the sound through an open backed cabinet is much as the sound from a sealed cabinet.

Clean is wonderful, distortion is crystal clear - even at high volumes, you can hear each note of highly distored chords - this is the nature of class A.

Many people comment that this is the best sounding amplifier for my acoustic guitar - really is magical and through the Univalve actually sounds like an acoustic guitar! This again is the nature of Class A - it is pefectly suited to the anomalies of acoustic guitars.

You have to learn how to use this device.

All I can say is one night, mid-gig, mid-song, I felt the rhythm guitarist trip over whilst doing his silly Pete Townsend imitation and turned around in time to see my 2x12 cabinet, with UNIVALVE atop falling over forward.

The amplifier hit the floor from nearly 3 feet up. It bounced. A peculiar fart was emitted from the speakers, and we kept playing. The Roadie picked up the speaker cabinet and left the THD on the floor, upside down, while we finished the last 40 seconds of the song.

At the end of the song, we picked everything up - all still powered up and running, put the amp ack on top of the cabinet, and got into the next song.

That was eight months ago. I found that one of the valves used in that 'experiment' died soon after and was buried with full military honours. The amp didn't seem to suffer any consequences.

I dropped a Marshall from 6" once getting it out of the car and it cost over $180 to get repaired.

Never had to deal with THD.

My tech did a review when I purchased it and recommended I purchase a new 12ax7. No issues h could see.

Been playing for over 30 years.

If someone steals it and I find them, we'll be having our own, very special "Good Friday". Then I would sell their hair to a wig maker and use the proceeds to immediately purchase another Univalve.

I had tried a Mesa Boogie and Ampeg - both were nice, but I found the Univalve had so much variety through the ability to instantly change a valve. There was NO COMPARISON with new Marshalls or Fenders I tried - but hey, brand and image is everything in the big, wide, wonderful music instrument industry!

The only thing I would change would be to include a footswitch for selecting high or low impedance inputs.

Serial number 1681. The amp debuted in 2001 to positive reviews. I picked this one up used, in excellent condition in 2008 from a private party. Featurewise, it's Class A, single ended with the unique (as far as I know) ability to accommodate a variety of preamp and power tubes without the need for rebiasing. In my book, you can't get any more versatile.

I've read the other reviews and I'm baffled by the negative (harsh) comments. In fairness, I play my amps as clean as possible, preferring distorting pedals to ad whatever "grit" I need at any particular time. So here's my setup: mostly single coil, Fender-style guitars (my current favorite is a Warmoth Fender with Fender noiseless cobalt PUs) straight into this amplifier's "Roll" input (low gain) without the attenuator active, High Voltage, "Attitude" at 12 o'clock, volume at nine, treble at 3 (this is a really bright Strat) and the bass at nine. It's like an eargasm. That means an orgasm for your ears. Duh. Crystalline, warm, three-dimensional, living and breathing notes spilling out of this thing in a way that makes every other amp I've ever owned sound flat and brittle, including my prized Fender Pro Reverb. I confess. I don't even know what kind of tubes are in this thing at the moment. It sounds incredible. Fantastic. Unbelievable. Spine-chilling. Warm, Breathy. I could sell every other amp I own (I started doing so today, after playing through this amplifier) and be perfectly happy.

Seems well built. No reason to think it's not reliable, but I can't offer an opinion on this topic.

No opinion. Buzz seems pretty positive on THD in general.

I've owned a lot of amps. I tend to buy, sell, buy, sell and buy, then sell. This one's a keeper.

Simple design with some twists. Low and high inputs, volume, treble, bass, "attitude" knob (adjusts the signal strength to the driver tube),full power/attenuator switch, the attenuator control, which is actually a THD Hot Plate (think Marshall Power Brake), hi & lo voltage switch, and a simple (but effective) noise reduction circuit. On/standby switch, and of course, mains power switch. Rear panel consists of speaker out jack, switch to toggle between 2/4 ohm, and 8/16 ohm speaker loads. Also a line out jack with its own level control. Single channel, no FX loop. Amp has the ability to accept any octal based power tube (6L6, EL34, 5881, KT66, KT77, KT88, KT90, 6CA7, 6550, and even 6V6,(amp must be set on lo voltage), and an EL84, with a yellow jacket adapter. Also, any 9 pin tube can be used for the pre-amp, and driver tubes, such as 12AX7, 12AU7, 12AT7, ECC83, etc. All this adjustability to tailor the overall character and response of the amp.

Well, this is where it gets harsh, literally. This is the 2nd Univalve Ive owned, and I had forgotten why I sold the first one, but was reminded after owning this amp again. I really cant understand why players seem to be gushing over themselves about this amp. I tried at least 20 power tubes (some duplicates, like 3 or 4 different EL34's) and an equal amount of pre-amp/driver tubes, and though the amps character DID change, I was NEVER able to get rid of the harshness of the overdrive/distortion in this amp. Its not the speaker cab (2-12, half open, half closed back cab, with G12H-30 Celestions)that causes this. It might be transformers, it might just be circuit design. There really is no clean sound, unless the guitar is plugged into the low gain input, and then the amp sounds somewhat weak. Its strong enough in the high gain input, but again, harsh sounding, especially in the lower registers of the fingerboard. Its not that the amp necessarily sounds BAD, it just sounds dry, and "grainy", and excessively bright; the amp does lack bottom end, regardless of tube choice. I ALWAYS had to run the bass full up, and the treble basically at zero, or 9 o'clock position at best, and even then, the low end was barely acceptable. Once the attitude is turned up, the brightness increases even more, along with the aggressiveness of the amp. Its an appropriately named control. It is a fairly loud amp, and it has a LOT of gain, just not quality gain IMO. The attenuator and the noise reduction work as advertised, but decrease the responsiveness, and attack of the amp considerably. Hi/low volt switch cuts the output approx in half, and also knocks down the responsiveness.

No reliability issues. It does seem to be built very well.

I spoke to Andy Marshall (THD amp designer) and he seemed very friendly and helpful. He recommended trying KT66, or KT88 tubes, which I did. Neither cured the harshness, or lack of bottom end punch.

Ive played guitar for 35 years, and have owned a LOT of different amps and guitars. Quite honestly, Im selling this amp this coming weekend, and I cant wait to get rid of it, and would NEVER buy another one. Im not opposed to trying other models of THD amps, such as the Flexi-50, but the Univalve is something I wont buy again. (and I got this amp DIRT cheap, at Guitar Center when they had an inventory clearance). There was a reason this amp wouldnt sell, at any more than what I paid for it, because no one liked the way it sounded. Im firmly convinced that there was nothing actually WRONG with this amp, as my previous Univalve had the same grainy tonality. Its just the nature of this amp.

This amp has one channel but it has a two inputs, one of which adds a gain stage for those who play with a lot of distortion (or weak pickups). You cannot AB the inputs because when you are plugged into the low gain input it defeats the high gain stage or something like that. There is no effects loop or headphone jack which would both be nice, but there is a switchable line/instrument out with a volume control, and when no speaker is plugged in, the amp supplies a dummy load, so it could easily be run into a headphone or practice amp, or your stereo's aux in, or any higher powered slave for that matter. You could plug it straight into a Twin. It has a Hot Plate -- kind of like a power soak -- which works best at mid volume, but gets a little tinny when you really crank it down. The amp can run any octal ouput tube with the same pin-out as a 6L6 (6V6 up to 6550), so you can fiddle with the ouput power and tone, and with an efficient speaker it would be loud enough for small clubs with the stock EL34, but I'd just recommend getting the tone you want and running the line out or a mic to the house system.

The features I was looking for in an amp were flexible tone, tube overdrive regardless of volume, and NO hiss or hum. I have vowed never to carry anything heavier than 30 lbs again, so I didn't want a combo. My favorite time to play is late at night, and when I am not playing a note, I DONT WANT TO KNOW THE AMP IS THERE, just like when you pause a CD player, you don't want to hear your stereo making extraneous noises. I tried new Vox and Line 6 modeling amps and tube amps. The modeling amps with a 12AX7 seemed good at first, but then I could hear the hiss being gated out. I also tried the new Fender Princeton Recording Amp and was impressed with the features. Any of these would have been good choices for playing live, but all failed the hiss test. I wound up buying the Univalve because it passed the NO hiss test (there is a noise reduction switch that is not a gate) and the tube overdrive criteria, but I had to do some experimenting to get the flexible tone.

There is really only one feature I wish this amp had that I can't invent a workaround for, and that is a drive control to let you adjust the amount of gain you are adding if you use the high gain input, so for now I don't use it, but I haven't tried any tube substitutions yet.

You will never get through all the sounds this amp can make once you start substituting preamp and power tubes. Plugged into the high gain input, noise reduction off and cranked you can make this amp a little more noisy, but nothing like a Mesa -- sorry, but NO hiss was one of my main criteria here, so there isn't much to criticize.

The amp is heavier on the mids than I like for playing either bright jazz or funk rhythm, but just right for lead. At first I thought I was going to have to use a second amp for rhythm, but I solved my problem as follows. My pickups are active EMGs on a strat. I plugged into the low gain input, turned the amp all the way up and set the controls for a good searing lead. Then I put a Danelectro Fish&Chips graphic EQ pedal between the guitar and amp (read the Harmony Central review on this little cutie), cut the mids out and dropped the master gain on the pedal for a 10 - 15 dB cut, just the amount I needed to dial back for clean rhythm tone. If your pickups aren't as hot as my EMGs, you could probably do the same routine in the high gain channel. The result is just like channel switching, EQ in for rhythm, EQ out for lead. You can use the hot plate to adjust overall volume.

I would use it without a backup. The tubes and controls are mounted on the chassis, but this amp does have printed circuit boards in it. Things are spaced out nicely inside, and power resistors are up off the board. I prefer point to point wiring but that would put it way out of my price range. My compromise will be just to open it up once in a while for the first few years and make sure the circuit board isn't getting brown (heat damage).

I bought this amp used on craigslist -- no warranty -- and had never played one before. I noticed that the hotplate cut out when the knob was turned all the way up. I called the Seattle factory and talked with the guy who designed the amp, Andy Marshall. He emailed me instructions on how to clean the rheostat complete with pictures. He offered just to do it for free if I brought the amp in. The instructions were good enough for me, but if you don't want to open your amp up, you could print them and take them to a tech.

If you take an amp back into the isolation room in your favorite music store you will learn more about it than you can on the show room floor with all those other players wanking on the Marshall Stacks. I have been playing since I was 10 and building amps since I was 12 (49 years old now). I have built and owned dozens of tube amps and I had pretty much come to believe that more gain stages equal more hiss. I cannot figure out how THD made such a NO hiss amp, so if I lost this one I would have to just buy another. Granted that I had to use a $40 pedal to make it act like a channel switching amp. I think my amp building days are over because of this one.

Great.....but no reverb! i give it a 10 because of the tube swapping and no biasing, which to me means no amp tech charging me money.

great tube saturation. i've been playing this amp for a year now, and i can tell you this: i've been the type to buy an amp play it for a year, sell it on ebay, buy a different amp and continue the same routine. i've been doing this for about 10 years now. i've had fender custom shop amps (bassbreaker) marshall jcm 800, ton's of blackface and silverface fenders, and many other amps. i always would get tired of the tone in a year or so and sell them in order to be able to afford another one. the only one i could not sell was a blackface twin that is the best twin i've ever heard (i've owned 6)
well a year later and i'm still in love with the tone that the thd gives me. if i get tired of the EL 34 sound hell i just throw in a 6l6 or a 5881. i will not be selling this amp, if a guy like me who is so fickle about tone can still fall in love with the tone every day for a year and not want to sell it, then that should speak volumes about the univalve. speaking of volume the 15 watts is perfect, i keep the volume turned all the way up and i'm never to loud but never get lost in the mix. you can hear some recordings i've made with the univalve at myspace.com/toddpirk all the songs on that site were recorded with the univalve. i used different tubes for each song too.

i give it a 8 b/c the light keeps blowing, bad fuse or something, but it does not affect anything it's just a light.

never dealt

been playing for 18 years, i think i will always be an owner of thd amps from now on, i love it! the price is just so good too, they could easily charge more for these amps and still sell them. i do wish at times it had reverb but thats what my fender twin is for i guess. great amp that univalve.

It has a lot of features, the hotplate is ok but as they all do at near max attenuation, robbs character severely. The lack of any loop on a techy sort of head like this bugged me to. You might think it would degrade the tone so it was left off? The hotplate should be left off too if that's the case. The high low inputs are vastly different in volume. While the high gives good volume, it's only good for a high gain tone. I have 5 watt amps that give twice the volume of the low gain input. If my ratings seem harsh, they're only in relation to the price of this amp.

It is a medium-to-high gain amp really and does little else worth mentioning. The tone was dissapointing and harsh, not musical at all. My array of 9 assorted power tubes changed the amount of gain but not that harsh, grainy honk. I have honestly gotten FAR tastier tube tone from a Sanamp Classic through a clean Fender Twin or Musicman RD50-112. That setup also takes a giant dump on the Univalve at speaking levels. I play Floyd Rose Mexistrats with USA electronics, Duncan little 59 HB's in the bridge pickup and Warmoth stainless steel fretted necks. I tried a ts808 with the Univalve which sounded OK but I was dissapointed that it was so much better than the amps tube grind. For the price and description, I didn't think I should need an OD pedal.

No problems at all. But I didn't keep it 2 months.

I've been playing over 30 years. I know classic tone, how to tweak knobs and adjust settings. I have several speaker and cab options. I tried everything. I loved and still love the look and portabillity of the THD amps. They look so damn cool but fell WAY short of my expectations in the tone department. The sound clips on the site were nothing like the actual tones available. I packed up my pile of new JJ's, the amp and the gigbag and sold it as fast as I could. I got my cash back before the word was out. I have owned Many tube amps, Mesa Mk3, Marshall DSL100, Fender Prosonic, Twin Reverb, Traynor yba-1, GK 250ml, and more. I have never unloaded any amp as fast as I unloaded that Univalve. My advice, try one first if you can or get a good price cause you might be selling it fast. It doesn't get good tone for the price, plain and simple. I doubt I'll ever try another THD amp.

The UniValve has 2 channels (Rock and Roll), but they are not switchable. Aside from that limitation, the amp is incredibly versatile, allowing you to freely interchange tubes (power and preamp) without rebiasing. The amp also has high and low voltage settings, as well as a built in THD Hotplate attenuator, so you have tremendous control over output level.

I own both the UniValve and BiValve, and they are my favorite amps of all time (and I've been playing for 30+ years). I cannot fathom how anyone could rate the UniValve low on "sound quality"! By experimenting with different combinations of power and preamp tubes, you can pretty much create whatever tone you like. No, it may not sound "exactly" like a Fender or "exactly" like a Marshall, but I don't care because I think it sounds better. And, if you should become tired of the Uni's tone, just change the tubes -- Fantastic. The UniValve (and BiValve) is also very responsive to pedals.

THD prides itself in state of the art PCB construction, and when you look inside, it appears every bit as well made as any boutique PTP amp I have ever seen. For 2 or 3 years now, I've played it 3 or 4 days per week, and have never had a problem. As an aside, it's also one of the most aesthetic amps I have ever seen -- sometimes I just want to stop and stare at it!

Playing classic rock 30+ years, and have owned too many amps and guitars, always looking for the perfect "tone." I've sold off a lot of good ones (vintage and boutique), but will never part with my UniValve (or BiValve). Moreover, at under a grand, this amp is a downright steal.

The 80 plus reviews here will give you the details here. I bought mine in 2006 with the Avatar cabinet deal. This is not my only tube amp-it fills a nice void with the features it has. I like the Hot Plate, I like the responsiveness of all the controls. Do not use the noise gate switch and yellow light at all.

They did switch the "THD" logo on the front from steel to white plastic. No big deal, but I liked the metal logo better...and yes you can put the top grill on with a KT88 in there.

I rarely use the "Roll" input. Sounds a bit thin with either my Strats or SG (or other humbucker equipped guitar). Big difference in volume between the two channels....i.e. if you leave volume at 'noon' setting, it is louder on the "Rock" input than the "Roll". No big deal. I run it with a JJ KT88 and JJ preamp tubes. This set up gives me a great Ronnie Wood Faces Strat tone and with a slight tweak, a great Duane Allman sound for slide and leads via the "Rock" channel. It does what my other tube amps do not. I have Groove Tube Soul-O 75 with GT6L6 GE tubes and a Savage Macht 6 with EH 6V6 and 5751's in it....so it fills in there. I also like it with EL34's-but not 6L6, 6V6 or the EL84's with the yellow jackets. Don't kill yourself buying and switching tubes like mad, I know that is the idea here with the Univalve-but pick a sound you can work with and go with it.

Very reliable and light. Be careful if you have kids, they can get their little fingers in there when you aren't looking! Tubes look cool to kids and the purple pre amp tube covers are tempting. No issues here. Have not had to change the little yellow/orange bulb.

Great. They forgot the power cord in mine when it shipped. Called Ed at THD, told him I got from Avatar (even if you do order through them, it ships direct from THD), he sent out next day. Never dealt with them other than that.

I love this amp. Fairly cheap for all the features you get for different applications. I would definitely check out the Avatar deal, their cabs are great for the money. I ended up running my GT Soul-o 75 through the Avatar 2x12, and now run the Univalve through a Mesa 1x12 3/4 back. Good for guys who have/want multiple amps...I just do not like the Roll input as much as the other. Maybe if I fiddled around with tubes all day, I would find a combination that would work for me using that input-I am sure I could.

Very versatile amp, you know the features

I guess it depends what you like. I found three combinations that were stunningly good, and a couple that were just average. Overall though it sounds great. You really have to tinker with it, it took me a week to find a combination that worked for me. I wish it had a master vol. I don't like the hotplate sound very much. Gives off a little hum, but nothing offensive noise-wise.

No problems. Excellent construction.

Very good support.

Great overall

If you're reading this then you're probably aware of the Uni's features. The big selling points for me were the self biasing and the built in Hotplate. The only thing I really wish it had is a mid control.

I'm currently using an Avatar 2x12 open back cab with a Celestion Alnico Blue and a G12H Anniversary. Guitars: Tom Anderson Cobra, Suhr Classic, G&L ASAT Z-3. It's tough to rate the sound of the Uni because it will accept almost any tube. I bought this amp without ever playing through it knowing(hoping) I could find my sound through experimenting with different tubes. Seemed like sound logic at the time. The Uni is very sensitive to tube changes so be prepared to do some experimenting of your own before you find the sound you're looking for. I have 2 or 3 tube combinations that I really like and I pretty much stick to those now. So, the sound...the Uni sounds wonderful from clean to mild overdrive, no problem there. If you don't normally play with a lot of overdrive this is a gorgeous amp, definitely lives up to the hype in this context, BUT...when you crank up the volume to the point were you start getting some power tube saturation things get a bit fizzy IMO. I've been searching for a good tube combination for heavy overdrive and I've had some success, but the fizz is always there. If I try to dial it out with the tone controls it ends up too dark. I suppose it could just be the nature of a class A amp. Whatever the case, I just don't care for the way this amp sounds overdriven, regardless of the tubes being used. I'm not the only one who's experinced this, visit Univalve.net and you'll find a lot of threads on this topic. My solution has been to use overdrive/boost pedals with a low/medium volume setting on the amp and it works nicely, but only after buying some pretty expensive pedals; Xotic RC and AC Booster, Xotic BB Preamp to name a few. I'd also like to mention the Hotplate because this is a feature that I had high hopes for. While it does a great job of allowing power tube overdrive at bedroom levels the tone is pretty far from what the amp sounds like with little or no attenuation, a bit of a let-down. I can't blame THD for this though. It's my understanding that it's the nature of the beast when using an attenuator. Bottom line is this: From clean to mild overdrive I give the Uni a solid 8. Crank up the volume and I give it a 6.

It rarely leaves my studio so I can't comment on it's road-worthyness, but it appears to be nicely overbuilt. Very sturdy metal chassis and cover. Feels very solid.

Never dealt with THD.

Ideally you'll want to grab a few different tubes and take the Uni for a test drive before you buy. Unfortunately that's not always possible. Again, IMO the Uni sounds great from clean to mild overdrive, especially with single coils. If you need more overdrive for hard rock/metal sounds the Uni may not be for you. The ability to use just about any tube is the Uni's big selling point and for just under $1K it's a good deal. It's very nicely constructed and one of the best looking amps I've ever seen.

This amp was manufactured in 2001. The serial is I belive #308. It is extremely well-built, although light enough to carry around in the NYC subway!

It has two channels, but no channel switching, no effect loop, no headphone jack, but it does not need any of that.

As it is known all around the world by now, this amp has the ability to take any octal-based power tubes (it has only one power tube socket) without re-biasing and it also takes any type of pre-amp tubes (two pre-amp tube sockets).

This amp is for experimenting and playing around with tube combinations til you find what you like. And you will like more than one combination for sure!

If you get 'tired' of one sound, go and switch all the tubes, or switch one tube, or two or all, and you will have something completely different coming out of the amp.

The amp has -in addition to two inputs (Rock and Roll), a volume knob, treble, bass, and attitude (it changes the edginess of the sound and your attack against the strings), it has a built-in attenuator, a built in and very hip-looking noise-reduction system, and a voltage switch to use with the different power tubes. The eq (treble and bass) are highly interactive, meaning that the more you turn them up the less middle you will have, the more you turn them down the more middle you will find. So the middle frequencies are managed through the tactful interaction between treble and bass.

I would like to change nothing in this amp, nothing at all. It is just what I wanted and needed. Nothing more, but nothing less.

I play/record/produce experimental Latin Rock mostly, though I usually gig backing up other artists. The amp suits everything that I play and more.

The rock channel is for louder, edgier, noisier applications. The roll channel is for the quieter, cleaner, chimmier stuff. Both channels are ideal for recording.

15 watts of pure Class-A tube power is pretty loud! Don't be fooled by the wattage. 15 watts is not quiet at all.

I wish it had a volume/master volume setup to drive the pre tubes for more variety. I wish it had a effects loop, you would think a kinda techy, frilly amp like this would. The amp is light and quite nice looking, The hotplate works well at reasonable attenuation.

The roll or clean channel is nice and likes pedals a lot but it only achieves about half the volume of the rock or gain channel. I would have probably liked this amp much more if the roll channel had more headroom. The rock side is slow and spongey with not much headroom or articulation. Not at all plexi like. It's closer to a cranked tweed deluxe sound. I have owned many near top shelf amps in this price range, Marshall DSL 100, Fender Prosonic, Mesa MK3, 70's twin Reverbs, Traynor YBA1 Bassmaster. The Univalve is not worth any rave in the sound category for the price.

Honestly, if you want a great low to medium volume plexi rock tone at an affordable price, get the cleanest sounding, loud and punchy old {70's Twin Reverb, 60's Sunn, 70's Traynor, or 70's Ampeg) tube amp you can find. Then get a Tech21 Sansamp (original or classic only). Many guys also swear by the Roland JC120 with the Sansamp because it's a loud, clean and indestructable (solid state) amp. This is the best affordable plexi tone I have found and I've tried a lot of 700 dollar amps in the quest. Plus it's easy to put effects between. A plexi clone? no, but way, WAY better cranked plexi tone than the Univalve. No noise because high power is clean power, the powerful amp is barely even trying. The Univalve is sweating it's ass off thus noisy. The Sansamp will provide better articulation and rich harmonic tone, loud or at TRUE, whisper quiet bedroom levels. Just try it, SAVE YOUR CASH, you'll see.

Did not have any problems.

I will never buy another THD amp. I tried it, it's nothing special for the price.

single-ended EL34 amp with built in attenuator

I hear lots of people saying that the Univalve sounds like an old Marhall plexi. Crap. These people did not own a plexi....the Univalve sounds nothing like a marhall. A Marshall will give you an outstanding overdrive as soon as you start cracking up the master volume (a different thing than having lots of distortion in the preamp....the one I am talking about is power amp distortion,which is what a plexi is all about).
The Univalve sounded sterile and too clean to me ,with it's master volume fully up.
It has none of the dynamics of a plexi.
The people that say that this amp will 'reveal' your sloppy playing (if you play sloppy) probably did not own a good tube amp before,and were too busy with their Boss Metal Master pedal crap.

Something else that I did not like about the Univalve: when it's cranked up and the attenuator is engaged.the sound was sort of coming and going....sounded unstable to me.
Overall,the Univalve sounds a little too cold for my taste. There are other good amps around. I will get a cheap pignose g40-v and will pay a tech to have it converted to EL34 valves instead of 6l6.
As this amp is based on an old Bassman,(old Marshalls were based on that too,they say) it should be interesting.

The Pignose costs a lot less than the Univalve. I am getting it as soon as I can

seems well built,but then again,at the price it should be.

as I said,it is too clinical in the power amp distortion area,for me,too cold

You can use virtually any tube you know off and adjust a degree of gain treble, bass and attack as you please ...

It depends on your valves: 10 if they are outstanding, or 6 if they are bad or old or 1 if they are dead.

WARNING: THIS IS NOT AN AMP FOR BEGINNERS or sloppy players as it is like a superb hi-fi systema nd does not pardon sloppy playing or less than perfect gear.

Some people rated it poorly as they have bad guitars or bad cables or (very critical) used cheapo tubes or (almost as bad) low-rate speakers.

This amp revals THE Truth about your gear, sound and playing so make sure you have everything on par.

Sloppy players and beginners stay out - or buy Line 6 or Roland gear.

3 years no problem

Great people - great community.

I use it mostly as my tone pre-shaping unit and plug it into one of my numerous other amps. Still, Univalve is THE best and most versatile.

If you have $850 and you are a SERIOUS about your SOUND and if you have some GREAT guitars and CAN play well - then simply - buy one !

I purchased my UniValve new in 2006.

Cool features: Line out: use it in the "Power Amp In" of a Fender Blues Deluxe. Increases the volume and accesses the Fender's reverb. I've also used this feature direcly into my 1964 Bandmaster head: very sweet sounds!!! Attenuator: seems to compress the signal a bit and drops out some of the highs, this is actually a good thing and I often use it on it's highest setting (e.g. highest volume) just to tweak the tone.

Bummers: No channel switching: I like to roll the volume back on my guitar to get the clean sound, but the hi-gain input just doesn't clean up as much as I would like. Being able to switch between the two would be great. However, with a 6l6GC tube there is more clean headroom.

No reverb: I have an analog spring reverb unit, but the Univalve's hi-gain input blows the sound up so much that it sounds like I'm playing in the Grand Canyon, and yes, I did turn the reverb all the way down. It's either off or Canyon city. However, it works beautifully for the low gain channel. Shame on me for not dragging the reverb unit into the store to check it out. Is this the deal breaker? No way!!!

I'm using a 2002 Gibson Special Faded Les Paul with Humbuckers played through a custom made 2X12 cabinet with Celestion G12L 35 watt speakers. I play mostly blues influenced rock. I was looking for the Allman Brother's sound. It took me about a week of noodling to find it...well actually what I have is a lot nicer in my humble opinion. It's smooth and creamy, lots of sustain, a very musical sound: no harsh ear piercing sounds. I set the amp volume at about 10:00 (1/3 volume) and the guitar between 7 and 10. The high is set very low (between 8:00 and 9:00) and the low is mid-way up. When I set everything at 12:00 (that would be 5 on normal amps) it was just way to bright and harsh sounding. The "Hi" nob is very sensitive between 0 and 3 and less so between 5 and 10.

This amp gets some amazing clean tones as well. However, with the EL34 stock tube a good clean Jazz sound is tough to get at stage volume. In a crowded club the vocal noise will be louder. With the volume all the way up, the amp distorts slightly bassed on how aggressive one plays. This sound is amazing, and wonderful for playing blues.

The reverb thing is hardly noticable until you stop playing or play staccato single note riffs. Pulled a blind test with the guys in the band. None of them picked up on the lack of reverb and were stunned when I clued them in. Don't really know why this is the case, but I like the sound. My Bandmaster has a similar effect but a more elastic / spongy feel.

The easiest sounds to dial up are the 70's-80's metal tones. AC/DC, Zepplin, The Darkness. Right out of the box my wife's jaw dropped and she said, "Oh, my God, that sounds exactly like AC/DC." Very fun to play, and if you've been trying to get this sound with any amp that doesn't have EL34s, then you will be stoked.

Warning: use your ear protection with this amp, don't be fooled by the wattage. Even on the 5 watt setting this amp gets very loud through the high gain input. If you play metal with a drummer that likes to play hard, this amp will not cut the mustard. On the other hand, every time I turn my Blues Deluxe up enough to get that nice power tube distortion going, the club owners run over pissing and moaning that the bartenders can't hear the drink orders: not so with the UniValve!!!!!

Overall I am delighted. I am planning on purchasing a KT-66 tube, but beyond that I'm not sure I would want many more sounds than what I already have. When David Geffen comes crawling back and begs us to accept his offer, I will buy a Flexi-50...and a BiValve...and a....

I've owned the amp for a few months...so far so good. It's built like a tank.

Haven't had any contact and haven't needed any.

I've been playing for... let's see 37 minus 10, ouch 27 years, what a cruel question to ask!!
I also own a late 1980s PRS Custom 24 and a Mexican Strat, however, I play the Les Paul most of the time. The best thing about this amp is that it get's the most amazing sounds at volume levels that are more reasonable. I practice in the basement of our house at night on the 5 watt setting and the kids on the second floor never wake up. Mom can watch the inane reality TV shows and chat on the phone during the commercials. Everyone is happy. This is not the case with my other amps. Fortunately, I play with some very tallented musicians who are all well schooled in the Jazz and Blues genres. Listening to each other is highly valued. As a result, I really do have enough volume. We played one gig in a medium sized theater. I ran the THD through the Blues Deluxe for a little extra stage volume, but the mic was in front of the 2X12. I could hear myself through the monitors no problem...kudos to the sound guys. It doesn't always work out that way. Finally, I tried out some very expensive "boutique" amps prior to this purchase. Bang for the buck this amp is untouchable!!

THD Univalve, manufacturing year unknown, but the serial number is #1336. Rock/Roll inputs, volume, treble, bass, attitude standby, Hi/Lo voltage selector, noise reduction, and power attenuator controls are on the front face; line out, speaker out, speaker ohm switch, and fuses are on the back. Most notable feature is removing the heavy-steel cage and trading out tubes to your hearts content. Very hearty construction, but you won't throw your back out moving it around. 2 pre-amp tubes and 1 power tube controls your tone. I presently have an unmarked 12ax7, an old Mullard 12au7, and vintage RCA 6L6 in the power slot. Rock, blues, country, jazz, and everything in between sounds wonderful through this head.

Given the ability to re-tube without biasing your amp as well as very touch sensitive controls, this amp is fantastic. Ideal for direct recording and live use, but not necessarily a road warrior amp.

I play a stock '04 Fender American Deluxe Strat, an '89 Les Paul Custom updated with Duncan 'buckers, and a Gretsch Electromatic Hollowbody with DeArmond 2000k single coils. All of them have subtle nuances that the THD embraces and amplifies. No more "everything sounding the same" when I play!! So far, I've been very pleased dialing in clean tones with the Roll as well as plugging into the Rock input and cranking the attitude knob. While you can get very loud with this amp, the controls allow you to use the tone and volumbe knobs on your guitar (remember those?) to achieve a smooth, compact tone that is very enjoyable at bedroom volume. I am also completely in love with the built-in Hot Plate attenuator to play with overdriven tones without disturbing the peace. If you're into metal, you'll probably want to check out the Bivalve or Flexi to boost your wattage. Otherwise, if you can't find a tone you like with the Uni, nothing is going to make you happy.

My Uni was brought in from a local recording studio when they decided to downsize their inventory, but it was used to good effect while they had it. Based on the research I carried out before, everything THD puts into the amp is designed to be more durable than any other manufacturer; this covers the wiring, the body material, fuses, and the overall amp to ensure that it'll last. I haven't gigged with this, but you'd have to throw it from a moving car to even dent it. As long as you have tubes (Heheheheheh) and fuses in your toolbox, this amp should last you for years.

After I bought my Uni, I wanted to build my own 2x12 cabinet and thought about calling to ask if they recommended series over parallel wiring. Called THD, and while the tech guy wasn't immediately available, the guy I spoke with twice offered to call me back or have me e-mail him directly and he would pass it on. I managed to get the info I wanted, but if I needed THD support, I'm fairly confident they would back up whatever I needed. There is also a dedicated group of THD users who post at univalve.net that can guide you through everything THD-related. Worth checking out if you're thinking of buying one of these.

I've been playing for about 15 years now, and I think that this may be the only amplified head I will ever need again. My new addiction? Tubes! Seriously, I went from a hybrid combo and an all-tube Epiphone Valve Junior to a tube machine that makes me realize what I've been missing. Although my ears aren't as trained as they should be and my playing skills are a little lackluster, you can really appreciate the difference in dropping a 12au7 in the driver position. See? Three months ago, I would have had no clue what that meant.

I was looking for this amp for a long time, and never saw one around. By chance I wandered into a local store one day and saw it used for a good price. At first, I kept trying to talk myself out of it by telling myself it didn't have reverb, that I'd have to buy a cabinet, surely something better must be out there. After three weeks of mulling it over, I couldn't get the sounds out of my head. I even brought my own guitars with me to the store, and it was the best sound they had ever made. Suddenly, the doubts became strengths: build your own cabinet, choose your speakers and be in charge of your own sound. Reverb? Playing in a room generates it's own reverb, no? A great-sounding 15 watt, hand-built, all tube, American guitar amp head for a reasonable price? Why was I trying to talk myself out of that?!?

Like a British sound? Thrown in a EL84 and slap it on Hi voltage. Love your old Fender? Swap in a 6V6 and keep it on Lo. Want your own sound? Load up on some old tubes from eBay, send the kids to camp, put the dog in the yard and tell the misses that she really should treat herself to some new shoes and spend the day putting your own mark on your Univalve with your favorite guitar; I think you'll like it.

i tried it in my local shop, but bought used. i like it's simplicity on the front, and i also appreciate what it has on the back. i find it very versatile for what i like to do. mostly i keep it at about 2-5 o'clock and it crunches nicely on it's own, but absolutely comes alive with my pedal setup. i haven't owned many amps, and only 1 other all-tube but this is an extremely responsive amp. it responds to everything from the slightest knob adjustment on your guitar to any variation in technique. it's awesome, with some obvious limitations that are easy to get around if you need to.

i've got a stock 93 gibson sg std. i play fuzzy stoner rock type of sounds, and with my pedal rig it's amazing. on it's own it wouldn't cut it for everything i want to play, but that's what pedals are for. my cabinet clearly can't keep up with this thing sonically, so i'm working on getting the goods in that area as well. i have a 500watt stereo power amp to beef up the volume that will be a consideration when getting my new cabs, but even with my crappy 2x12 this thing with my rig has me in acid guitar bliss everytime i plug in. it can handle a huge variety of sounds, depending on your speakers. i go from high end painful screech to superbassy sludge mainly thanks to my main pedal, an EH Micro Synthesizer. This pedal is insane. I also use an EH deluxe memory man and for massive sustain and feedback possibilites i have a little t.c. electronic preamp pedal. this amp rocks.

it always works for me

no experience here, but from what i read it sounds good

I've played guitar for almost 20 years now. I'd get another one if i needed to, unless i decded to buy the bigger one. i love it.

Wow. Pretty simple amp. Only 15 watts :( Are you kidding me. This thing is LOUD. I can not immagine you running out of volume. The 3 tubes are self bias-ing. Great head room. The amp really cuts through. Sounds like a truck. Everything is clear....even with alot of gain.

Gibson Les Paul Custom '1975 and an ESP Vintage Plus with EMG's. This amp does not care. It makes whatever you have sound like it's supposed to.

Haven't had it long enough.

I love it. I bought it from Avatar speakers for $600 and also purchased a 112 cabinet with a Celestion Vintage 60 (Hellatone) speaker for a total of $812 delivered. Smokin' deal. Geat gear

This is 1-yea follow up review of this amp. The features have not changed, and I still love what it has.

I have purchased a veritable cornucopia of fine tubes, NOS GE's Sylvania, you name it, I know own them. I always run back to the stock GT6l6B. Although I do love many of the other tubes, the sound is VERY subjective. If you get one, you need to experiment with not only different power tubes but also the Input and the Driver tubes as they may a world of difference even with the same power tube. None the less, whatever tube I've run in it had it's bright spots with every guitar and on just about every setting. The only disappointment I had was a Telsa JJ6l6 (which I bought off ebay and it simply could be a bad tube). BUT...the sound....my god, clean and soft to dirty and wild. there is NOT ONE BAD AREA in this amp. I will say you may find the Hotplate to be a tad too compressive with bigger output tubes, 6550's and such. Solution, run 6k6 or 6v6's, turn the plate voltage to low, and don't run the hotplate...WOW!

I have not been abusive, but I have also not treated it like a baby. It's my work amp...I need to play it....I play it...I pack it...i play it..i pack it. It's NEVER failed. NOT ONCE! It's forgiving and doesn't complain. Good tubes on hand, I wouldn't worry a bit. I never take a second amp (Call me stupid-but i don't feel i need one).

Well as I predicted, THD customer support has been OUTSTANDING at answering EVERY one of my stupid questions. ED is like my long lost brother keeping me in line, helping me not make stupid mistakes with my Univalve and giving me extraordinary guidance and suggestions. AND GET THIS......My amp is not under warrenty since i bought it used, but I still get treated like I bought a 1000 of them! Good luck getting ahold of fender or marshall...Mesa Does return your calls and helpful, but not like THD. i get consise info from ED within hours of sending him an email. I'm Saving my money for the flexi 50 to add to my collection just so i have something else to bug ED about for another year! THANKS GUYS!

This is an awesome amp. I would not have it for my ONLY amp because sometimes you just need the AB push/pull thing or that old fender recto sound. BUT....it is MY MAIN AMP. MOST TIMES MY ONLY amp, and IF i was faced with getting rid of everything except ONE AMP, this would be the one i'd keep. I have friends who are marshall guys, but we agree that a band has to have diversity otherwise you just blend...they have not respected my choices in amps (mesa-legend-fender, etc), however EVERYONE LOVES MY UNIVALVE like I do.

I think every knows but simply a one channel class A tube amp. Rock (high gain) and Roll (low gain) input choices, volume, trebble, bass, attitude (gain), attenuater(hot plate), high/low voltage switch are your only controls. I use this in my home studio with a 2x12 cab loaded with Tone Tubby Alnico's. This amp at 15 watts is way more power than I need. I add effect at the board so no need for a effects loop. My only beef is with the very cheap tubes that were factory installed. Change these right away or at least pull them out and reinstall them as they can come loose in transit.

I use a American Fender Strat Plus with Fralin pickups, a Gibson Les Paul Class 5 with stock Burst Buckers, and a Heritage 555 with P90 type humber size pickups. This is where I could write for days. What sound do you want? This amp will cover them all if you put in the right combination of tubes. You will have to be very patient though because there is a lot of tweaking that will need to be done on both the amp and your guitar. This is a very bright amp so be prepared to turn the trebble way down. You may have to turn the volume down on your guitar as well, be patient.

When it comes to tubes do your homework. I went on line and found out what tubes were in the type of amps I wanted to sound like. Be patient you may not like the tube with one guitar but try all your instruments. I have found sounds I wasn't expecting and been very happy with.

Speakers are just as important part of your gear. Find ones that you like that can handle more than one tone. I tried my friends Univalve through my Marshall 4x12 1960A cab before I bought mine. Although it did drive the cabinet it sounded better when I switched it to two speakers. It became more punchy and the low end really came alive.

This is were I thought I had an issue but upon further review it was a bad tube and the fuse did its job. I bought this amp new a month ago and it comes with a 2 year warranty. With all the power tube changing that I do I might need to have that looked at in a few years. I don't take it anywhere so it will probable last for a good long time.

I have not dealt with them but a friend did and they did right by him.

I have been playing for over 20 years. I have been in bands done the gig thing. I have played Fender, Marshall, Boogie, preamp and rack gear, and now THD. All were good but you would have to sacrafice one tone for another or half you garage space. With the Univalve you don't have to. Just switch a tube and you have a completely different tone. I would buy another one if it were lost, stolen or god forbid broke down. This is just the most fun amp I have ever owned. i hate to sound like an old fart but you might need to be older to appreciate this amp to its fullest. You have to be patient and the tone will come to you.

Nothing new to say here. It's just about everything you might need in a high-quality, single channel amp. The controls are all very powerful/useful, the amp is very sensitive/multi-dimensional, and the Rock & Roll inputs provide a two very different tones to work with. The built-in Hot Plate is very useful if you need to control volume-to-gain setting, and having it built right in to the amp head is very convenient and portable. No reverb, but I use a pedal for that.

'89 Strat Plus Deluxe w/Van Zandt Blues, mid-'90s Epiphone Casino, mid-'90s Epiphone Les Paul Custom with SD JB/Jazz >> TU-2 >> Barber Direct Drive >> MT-2 Metal Zone >> Xotic AC Booster >> Xotic RC Booster >> Yamaha MagicStomp >> Univalve >> Avatar G212H. Mostly rock music -- all eras. To me, the most remarkable thing about the Univalve is that it must be one of very best high-quality tube amp values on the market. Even if you aren't shooting for "bedroom-level" tube tones or needing wide versatility in a studio setting, this thing is just a great single channel tube amp for playing live. I play through the Roll input with JJ 12AX7s and a JJ EL-34L, set the amp for a basically clean tone with a little hair on it, and use pedals from there. With the possible exception of extremely loud/extremely clean (given 15 watts and the inherent headroom limitations), you can dial in a wide range of base tone/volume combinations. I would think the Univalve would also be an ideal "dirty/crunchy" amp in a two-amp A/B approach as well. Either way, I haven't seen anything else that delivers this kind of quality and versatility for under $700.

So far, so good. I've had mine for four months and used it fairly extensively. Seems very well made.

No experience here.

I've been playing for 18 years. The Univalve is a stellar amp, and I would definitely buy one again.

My Uniivalve was made around 2003 in Seattle. It's a single-channel Class A tube amp with one output tube slot and two for preamp tubes.

The Univalve doesn't have four channels, on-board effects or many other bells and whistles. Yet it has a feature that trumps all that: The ability to take a wide variety of pre-amp tubes, plus just about any octal output tube you can find. You can also use nine-pin types likle the EL84 with an adaptor.

Some other great features are a built-in attenuator, a very effective noise reduction circuit, a dummy load, two input for high and low gain, a voltage selector switch and a very effective line-out with adjustable level.

The only feature that would be great is some sort of way to switch on the fly between the high and low gain inputs to have psuedo clean-to-dirty switch. Right now, I just roll off on the guitar's volume knob.

I use Duncan-loaded Charvels (old Japanese models) for my band, which plays originals that are like The Refreshments meets the Scorpions. Since I do most of the lead work, I aim for a great high-gain tone. Using a 6l6GC output, a Telefunken ECC83 and a GE 5751, I get a distortion out of this thing you wouldn't believe. Nice low-end thump with beautiful sustain for the leads. An Ibanez TubeScreamer fattens it up a touch.

Whoever thinks the Uni can't do metal just hasn't figured out what tubes to use. This is certainly not a Bogner or an Engl, but it does a nice early Metallica sound if you have the right tubes, guitar and pickups.

The longer the gig, the better the Uni sounds, and it loves being dimed.

Between songs, I hear no hiss or other extraneous noise out of this amp. Even in venues that often create a lot of interference, it stays quiet.

After raving about the distortion, I plugged some 6189 low-gain tubes into the Univalve and turned it into a blues player's dream...very clean with just a touch of breakup if I attack the strings hard.

The attenuator is decent, but the Uni sounds better without attenuation. This amp reacts very strongly to different tubes, so take your time to experiment.

I am running this through an old Crate cabinet loaded with Carvin's version of a Celestion V30.

I've only had it about two months. After two practices, the output transformer died. THD replaced it and said it came from a batch that had a less reliable transformer. Since then, it's been running like a Swiss watch. Also, it had been sitting at a guitar shop for a few years, so I don't know how many people who don't know how to properly operate a tube amp may have handled it.

I won't gig with ANYTHING without a backup...guitar, strings, tubes, picks, etc. If I'm getting paid to play, I am going to do anything possible to finish the gig no matter how confident I feel in the gear.

I'm leaving this category as "no opinion" because I haven't had it very long, and it really seems my problem was kind of an abberation. If you like, I'll update in six months or so.

Every company is occassionally going to have a product that fails. I hope they all take care of it as well as THD did. They are pleasant, prompt and thorough. Not only did the replace my transformer in the incident mentioned above, but they upgraded some wiring to their current specs. And they didn't once act like my constant questions were a pain in the a**.

I have been playing for 16 years. My current band has been together just short of two years. During that time, I've gigged and practiced with a Marshall Jubilee, Laney AOR100, TubeWorks RT-2100 and a Line6 Spider II (borrowed!). The Univalve has given me by far the best tone of the bunch. The fact that I can drive it at near maximum output and get that great output distortion does it for me. And it's tiny, about the same footprint as a large laptop computer.

If someone stole it, I might scrape together a bit more money and go for the BiValve, which has double the wattage. That might help for some larger venues if they don't mic us...saves me from slaving it to my TubeWorks head. Plus I can still pull an output tube for smaller venues with no adverse effects (not true with all tube amps).

Seriously, this is a terrific product from a great company. They also have a great user forum (www.univalve.net) where people who own them exchange ideas and advice. Plus you'll have a tool to shape your own tone. And it's not even that expensive at street price ($845) and good shoppers can find an even better deal now and then.

The THD Univalve is an odd creature when it comes to features, for it manages to have both few and many all at once. At heart it is an 18 watt all valve boutique amp, designed for studio/ small venue use.

While the Univalve is a single channel amp, it offers both a high and low power input, labelled "rock" and "roll" respectively. The High power input offers everything from a raspy brit gain to a smooth hard rock distortion. The low power input has a beautiful clean tone to a crisp, bright crunch.

The tonal options of the amp appear somewhat limited, having a Volume, Treble, Bass and Attitude control. Each control gives quite a small range of tonal variation (your not going to get a good 80's hair metal sound out of this one) but saying that, the sound that is there is well balanced, warm and probably the best all round tone I have come across. When I purchased this amp I compared it directly to both a Mesa/Boogie Rectoverb combo and a VHT combo (can?t recall the model on that one) and I would have to say that neither had a shadow of the depth and richness of tonality that the Univalve can offer.

It is also worth mentioning that never before have i played an amp that responds so much to playing dynamics. The diversity of sound and tone that can be achieved through your guitars tone controls and your playing here really is amazing.

The interesting part of the Univalve is the built in attenuator, THD's Hot Plate. When turned on this allows the volume to be raised, so pushing the valves, without the added decibels. In a home studio environment this is one of the most useful features that you can ever have, especially considering how well it works. It also has a noise reduction switch, which dose just what it should without sapping any of the amps tone

In summery this is a very "pure" boutique amp, designed with the home studio in mind. In this roll their really isn't anything that THD could have done to improve the amp. Saying that, do remember that it is an 18 watt head and relatively tonally restrictive. If you?re looking for sweet Jazz/Classic Rock/Blues tone for your home recordings then this amp should be a serious consideration. If, however, you intend to play Black Metal or live at anything more than a house party then the Univalve is probably a little too "pure" for what your looking for.

I'm using three guitars at the moment, a Fender Jazzmaster 62 Reissue (the Japanese One) with standard hardware, An Eppiphone Les Paul Standard and a B.C.Rich Warlock with BDSM humbuckers.

The Jazzmaster sounds great, with its single coils offering a great range of tonal options that all sound just as they should. Surprisingly it also holds its own with the heavier sounds, offering a great classic rock tone (think Zed Zeppelin's Black Dog or Rock and Roll). The humbuckers of the Les Paul offer a warmer fatter tone, that sounds great clean, but gets a little murky when on a higher gain setting (but this is somewhat the nature of this axe, which is soon to have EMG's installed). The Warlock also offers great clean tones and a rich think gain great for old Black Sabbath and other pre NWBHM metal.

The noise produced is minimal, and the added noise reduction function eliminates even the rudimentary single coil hum.

As previously mentioned the sounds are great for all non Thrash/ Black/ New metal styles. I play a mixture of music including the Red Hot Chilli Peppers, Led Zeppelin, Black Sabbath, BB King and the Smashing pumpkins. The Univalve is great for the entire above, bar possibly some of the heavier elements of Sabbath, as it can lack a little bottom end at the lower volumes. I also play a little Metallica and Iron maiden, both of which I use my Yamaha DG1000 for, as the Univalve really doesn?t do that kind of high gain.

The clean channel can be played at max volume without any break-up, however the attitude control can give it a crunchy edge if that is desired.

The distortion is warm and sweet, not heavy, this head is great at singing sweet warm gain, but doesn?t really do the brutal metal thing.

I have never had a problem in the three months that i've owned the Univalve, otherwise theres not much that i can say here

All of the Warranty side is done at my local dealer, so i havnt had to deal with THD at all.

I have been playing for six years, and have owned several amps during that time. The THD is by far the best purchase that I have made to date. That?s not to say that this is an amp for everyone, but for those looking for tone over features, and wanting to record in a home studio environment I would strongly recommend trying one of these out.

If the amp was stolen I would snap another up without a thought. There really isn?t anything else out there that can directly compare to the sheer quality of tone and build that THD offer.

I love that it is a compact, pure valve amp that reminds me of why I wanted to play to begin with. There are all to many amps out there these days sacrificing quality for an abundance of often useless novelty features ( like the Line 6 Vetta) so its a blessing to see such a great little amp make a stand for quality tone and playing skill.

I would also say that the amp has helped further me as a musician, as I have learned to use my playing and guitar to create the sounds that i desire, rather than resorting to digital effects.

When I purchased I compared this to the Mesa/Boogie Rectoverb and a VHT 50 watt combo. While both are great amps in their own right, neither could match the amazing 3D sound that the Univalve can produce, and with the added bonus of the attenuator the Univalve won hands down.

In some ways it would be nice to have more power so that the Univalve could be used for more live work, however this would somewhat defeat the object of the amp (THD do make larger output versions, but in my opinion they lack the quality of tone that the Univalve has)

Hope this helps anyone who?s thinking about getting one of these. Also THD's website has plenty of audio tracks of their amps, of if you think this might be what you?re after I?d recommend a visit there.

All the features on this amp are for tone adjustment. And it has plenty. With a amp this bright, the tone adjustment makes a big difference. Treble, bass, volume, attitude, hi volt, low volt, rock or roll input, hot plate. I like to call the knobs, "tone removers", you have to remove the tone and brightness in certain places or its just to much. I think we all perfer to have "to much" not "to little." You find yourself working backwards on this one.

I didn't really care much for swapping tubes. I spent $200 bucks just to realize the one they had in it was the best. If I needed to change my sounds it's easyer to do it with effects and stick with the cleanest sounding tube (EL34) for me. Yet the tubes do change the sound and it's nice to have one more thing to adjust. You can never have too many options.

Well, Im a metal head, at home hobbiest looking for the best sounding all around amp. The best thing about this amp is, it has incredible clairity. Bright clean tone and punch! I match it with a carvin maple top and a 2X12 thd cab. It is has so much clairity my frigen eye balls vibrate. Dripping in tone is a good description simply because the amp is very very bright and clear. However, It puts out exactly what you put in, including effects. If you have cheap effects or a crappy guitars this amp = "trash in - trast out."

Use good equipment and fine guitars and this amp will bring just that.
It is like a true old school no BS amp. What you put in is exactly what you get out, including effects.

I have found this amp will play any type of music. Its like a perfect platform for whatever sound you want. I like metal and wanted clean clear professional hi gain distortion and or liquid bubbly cleans with delay and reverb so I had to add effects. no problemo.

I remember someone in hear said not to use pedels. Nothing could be further from the truth this thing was made for pedals. Just don't overdrive it or put distortion on top of distortion, usecommon sense.

I also like to bypass all effects for the natural clean tone of my carvin guitar. Ahhhhggghhh! The crispy bright tone! You must try this amp.

Perfect.

TBD

My long endured search for gear ends with this amp + I added a rocktron prophesy tube preamp with effects. It's like matching two of the finest instruments. Now I have "angus young" and and "dimebag" forever on tap with absoulte quiet clairity. No hiss, no pop, no fuzzs. I just need to add a prgrammable footswitch and Im done.

Mine was likely made in 04 or 05, serial #1782. If you're reading this I'm going to guess that you know all of the features.

I selected it based largely on reviews here, and had never actually heard one until I got mine. Oh my...to those of you that spoke highly of this amp - thank you! This is the amp that I've been searching for.

It has all of the features that I was looking for, and there isn't anything on the amp that I won't use - it's a nice fit for recording or gigging as is, and works well with everything I've put in front of it.

It has plenty of power, at least for what it is designed to do. No, it's not going to fill an arena with bleeding eardrums, but it sure can get loud enough to be heard in any blues venue I've ever been in.

I'm using a Les Paul Custom with '57 humbuckers, a PRS with stock HFS pick-ups, and an old strat that's pretty much stock.

I'm using the amp for country, blues, and rock. Think SRV or Gibbons through early VH. For a little added crunch I've got a Fulltone Full-Drive, and I'm also using a Vox wah - that's it.

With every bit of gain poured on, sure, it's noisy. It is quieter than my Marshall with the same amount of gain, and is really quiet played clean. The noise reduction does seem to suck a little tone, and the attenuator does too, but it's a compromise I suppose.

With the volume rolled off the guitar just a bit the clean channel sparkles, and full on it has just a little edge. Switching to the "rock" input it has a great tube distortion on it's own, and it's really articulate. Again, it's really volume sensitive, and a little tweak here or there with the pick can get a great result.

It won't get dirty enough for metal, at least not to my taste, but that's not what I was looking for or expecting.

I'm not going to blow smoke up your ass and tell you that I've owned a ton of boutique amps...pretty much just marshalls and fenders all my life with the occasional peavey - all pretty good at what they did. This one is just a little more sensitive to attack and feel than I've ever experienced. Someone said that this amp will force you to play better, and I have to say that I really agree with that.

Mine is pretty new, but it's built to last. I wouldn't gig without a few fuses and a spare set of tubes, but other than that, I'd trust it. That said, there will always be a back-up amp...I just don't expect to have to use it.

My e-mails have been answered promptly, and Andy has been friendly and helpful. My gut feeling is that he'll stand behind his work, and I'd do business with him anytime.

I've been playing since 1979, and gigging since 1982. What other gear do I own? Just what you've read above I suppose...I don't have the funds to warehouse a bunch of stuff, so what I've got is what I use. I've still got a marshall that I'll probably part with soon, but only because I have what I need.

If it were lost or stolen I would most certainly replace it.

The sound is what I like the most about this amp, but there's also a lot to be said about the quality and the size. I don't have the luxury of a road crew...and I'd rather spend my time and effort playing rather than lugging gear all over the place. This thing weighs less than 30 pounds, and just put a marshall out of work - it has a better sound for my style and taste, something I never thought that I'd say.

Yes, I compared it to several things. A Line-6 pod pro came and went (quickly) and I demo'ed several Marshall combos and a couple of the new Fenders. Like I said earlier, I don't have money to blow on gear - I need to get my sound with a few good pieces rather than a rack full of stuff. Years ago I had an 18-space rack loaded with toys, and didn't have half the tone I have now. Being essentially a simple player and a lazy bastard to boot, I needed to simplify, and I have.

I saved a long time to get this amp, and it was worth the wait.

This amp has very few "features" but it has a wide range of excellent tones, depending on what pre-amp and power amp tubes you put in.. Extremely well built too.

Many excellent sounds with a wide range of guitars (humbuckers, single coils both strat and tele). Noisy at very high gain but that's only to be expected and the built-in noise reduction circuit works well. Swapping the tubes and fiddling with the dials makes for many hours of audio fun and it's quite inspirational. I have a Phillips JAN 5751, a Mullard 12AX7 and an RCA 6v6GT in it at the moment and can say, "so THAT'S what all the buzz has been about those tubes..."

It seems to be built like a tank so I don't expect any problems. It had an excellent reputation for build quality. I've had it for two months.

I bought it (and got a great deal) from Avatar Speakers (www.avatarspeakers.com). It was the best deal I could fine and it's paired with one of Avatar's excellent G212H Special 2x12 speaker cabinets, with one Celestion Vintage 30 and one Celestion G12H30 70th Year Anniversary Special. $659 for the Univalve and $278 for the cab for a total (with shipping) of $971

Playing for 30+ years, gone through a whole bunch of toys including Fenders, Marshalls, Mesas etc. and this seems the best of the lot. I chose this over a Mesa Lonestar Special. The only, repeat only, problem with this amp is the $$$ I've been spending buying NOS tubes to try in it. I've managed to get a few good deals of some old Mullard, Amperex and RCA tubes but you really have to shop around because some tube sellers will really screw you for something like an old Mullard 12AX7.

non sto a ripetere quanto gia detto, il punto debole di questo amplificatore e il riduttore di potenza, che essendo un semplice reostato rovina il timbro del suono a qualsiasi settaggio. non e paragonabile all'Hotplate. condivido l'assenza del loop, in quanto la filosofia del progettista e di ottenere il miglior timbro valvolare senza perdite di segnale. per l'effettistica si puo utilizzare l'uscita slave collegata a multieffetto e finale stereo (triamping).
si sente anche la mancanza della possibilita di cambio canale immediato, ma sarebbe comunque inutile vista la differenza di volume esistente tra i due canali.
io uso l'amplificatore in casa, ma con una KT88/6550 nella sezione finale e la cassa adeguata, c'e abbastanza volume per suonare col gruppo.

uso diverse chitarre: PRS Custom 22 s.t., Les Paul Special P-90, Stratocaster Std. del 1990 con EMG DG-20, Replica strato '60 della liuteria Jacaranda. il mio stile di musics spazia dal pop-rock all'hard rock, con divagazioni sul blues e rock-blues.
l'amplificatore e abbastanza silenzioso e non necessita dell'inserimento del riduttore di rumore (forse in registrazione sarebbe utile). l'amplificatore puo fornire tutti i suoni necessari per i generi sopra descritti. per l'utilizzo dal vivo e necessario munirsi di pedaliera effetti con distorsori e overdrive, in quanto sarebbe possibile usare solo il canale pulito, per avere un bilanciamento di volume tra i vari suoni.
il suono in generale e molto bello e dinamico, si puo variare il timbro grazie alla possibilita di usare diverse valvole sia preamplificatrice che finali (la EL34 da il crunch migliore, la 6L6 il miglior pulito, la 6V6 GE i migliori suoni vintage-style con la strato....etc.)
ho letto le recensioni, molti lamentano una eccessiva chiarezza del suono, distorsioni fuzzy etc. io stesso stavo per rivendere la testata, finche ho capito che e FONDAMENTALE accoppiare all'ampli la cassa giusta (piu che altro i coni adatti). la soluzione migliore, a mio avviso, e una 2x12" con Celestion G12H-30: niente piu suoni acidi o fuzzy, sia i puliti che i distorti vengono riprodotti in maniera eccelsa, sembra di suonare con un amplificatore diverso. il suono buca il mix benissimo, ma i bassi sono definiti e potenti e gli alti sempre rotondi e musicali, per dosare i medi, dato che non c'e controllo di tono per queste frequenze, basta ridurre un po i bassi e gli alti. a me piace il suono con i controlli di tono a palla, sia sul pulito che sul distorto, ne viene fuori un suono ricco e potente.
con la cassa giusta non e necessario usare valvole a basso guadagno per arrotondare il suono, provare per credere!
si possono ottenere distorsioni anche molto elevate, ma le migliori si ottengono settando l'ampli su un crunc e aggiungendo un overdrive o un distorsore, quest'ultimo tarato con poco gain.
e un amplificatore che a seconda delle valvole usato puo somigliare ora ai Fender, ora ai Marshall, ma ha un distinguibile timbro personale molto bello con qualsiasi valvola.

la costruzione e i componenti usati sono di prima scelta, ha fusibili di protezione per alimentazione, filamenti, anodica. a me e andata una valvola in corto e si e bruciata, l'ampli non ha avuto il minimo danno grazie al fusibile dell'anodica che e intervenuto (bruciandosi) immediatamente. il cablaggio interno e un capolavoro di progettazione ed esecuzione, io lo metterei nella categoria dei boutique-amps, pur avendo un costo onesto.
il case, oltre ad avere un'estetica a mio avviso perfetta, e robusto come un carroarmato.

mi e capitato di richiedere informazioni, sia all'importatore che al produttore, mi hanno risposto in pochi giorni e in modo cortese ed esaustivo.

tutto considerato, e un ottimo acquisto. credo che amplificatori del genere aumenteranno di valore col tempo, alla stregua dei famosi Fender e Marshall ( a proposito il progettista e costruttore si chiama Andy Marshall, che siano parenti? :-)
dimenticavo, ogni pezzo e autografato dal sig. Marshall e la firma e protetta da una mascherina di plexiglas.
e un'amplificatore progettato per gustare il timbro valvolare nella sua pienezza e per registrarlo. poco adatto per l'uso dal vivo e non versatile come altri amplificatori "moderni", ma che si puo comunque adattare ai diversi utilizzi, come detto sopra.
in definitiva, un apparecchio per palati fini.

For what it is supposed to do, it has all the features it needs. I believe this is a recording amp designed for studio use. That doesn't mean it can't do other things, it just means that its feature set reflects what it was designed to do. Based on that, it deserves a 10. But, overall, its feature set is limited and somewhat frustrating when out of its intended environment - the studio.

Using a Am. Std. Strat, old Duo-Sonic with S-D humbucker in bridge, old Musicmaster, '70s Les Paul, and others. The best match for almost any tube combination is my MusicMan Axis SS, unbelievably rich and versatile...so sweet.
For country, blues, '60s and '70s rock, reggae, jazz, modern jazz, punk, and, with effects, anything else, this is now an essential link in almost everyt guitar that goes into my console.
It's noisy with single coils and at crazy high-gain settings. What isn't?
Without the ability to add post effects at the console, it would be limited to just the rich pure tone it so accurately generates from any guitar. The tubes do change the amp's response pretty dramatically, but all the combinations I've come up with do sound somewhat similar in their purity and dynamism. The different tube combos are more of a nuance-type thing, not as drastic as some would have you believe. When you push them too hard it can get a little raspy, but raspy is good for some stuff.
It just sounds great. You can set the amp any which way and randomly twirl the guitar's knobs and it still sounds great. While it decently emulates certain classic tones, for me every goddamn note sounds great, regardless of settings. I've spent way, way too much time and money trying to find the tone this amp gives me in spades. I use a 2x12 with a variety of speakers, this creates an abundance of variety, sometimes too much...if that's possible.
You can run anything through this amp as well. It fills out some drum machine crap really well. It did wonders for a thin stand-up bass pick-up I was having trouble with.
The amp does sound best when not using the attenuator. It is too loud for many home studios.
If you A-B it with a Pod, you will wonder why you ever thought the Pod was worth a damn. Night and day.
I generally record electric guitar tracks on three channels, one mic on each of the dissimilar speakers, and one track from the balanced out. Among those three and in combination, it gives me great sounds in the monitors and on finished tracks. It is a must-have for any serious studio.

If you're gigging with it, bring spare tubes and fuses. Otherwise, it's bullet-proof.

They're cool and they stand behind their stuff. I've never had a problem but I've heard they go out of their way to take care of customers who have problems.

I'm a 30 year veteran of rock, hardcore, and, now, "Americana". I have had a home studio for 20 years. I've owned roughly 40 amps, from vintage Fenders, Gibsons, and Ampegs to rack-mounted, stereo multi-effected monstrosities. This amp does just about anything, in the studio, that any of the others did, only much better. It's definitely not as convenient as a Pod or plug-ins, but the results are worth the extra effort. It has more texture than any amp I've heard. Switching around the tubes is fun, but switching around guitars is even more fun. You'll see when you buy one. You can go completely insane with tubes and get into bidding wars on eBay over a blackened old Coke-bottle tube from Australia which may or may not work. I find myself hiding my favorites when idiots are coming over to record. It really is a dangerous obsession and sometimes it's hard to discern which damn tube you have in the dang thing.
I hate the flashing noise reduction light. I hate the grid voltage switch's proximity to the standby switch, the most frequently touched part of the amp. I hate the two inputs rather than a switch. I hate the fact that to get some sounds you have to destroy your hearing or suffer the tone-kill that the attenuator subjects you to. It would be nice if they provided an EL84 yellow jacket for free.
I'd have a replacement overnighted if it were stolen.
It's a great amp, it will change your life for the better.

I won't repeat what you can read in dozens of other reviews.

See below

Rock solid.

Haven't had to deal with them. But I'll tell you this: It's the first time in my life I've felt like writing to a manufacturer and just tell them how much I lover their product. No wait, I did write something like that to my girlfriends parents at some point.

There are a lot of reviews about this amp posted here already, which is not surprising, since it is so inspiring. I think it's the rare case of a product that has a very bold individuality, but at the same time adjusts to just about any user's needs. This combination of straightforwardness and versatility is truly lovely and rare.
I have also read critical remarks here, and I would like to react to some of them. One of the important things to know about the Univalve is that you can't just plug in and dial up any sound, which is what more and more people seem to expect these days, knowing only digital modelers. If they had more experience with the legends these modelers are trying to emulate, they'd understand that with any true tube amp, you have to put in a little work to get to your sound. This goes for setting up and adjusting the amp, but even more for your playing technique. But that is ultimately what making music is all about. No classical guitar player would expect to get a "great" sound without training his fingers to coax it from his instrument. The Univalve is relentless in a way, since it gives such a clear, unaldulterated impression of everything you do. And that includes all the little slips and boo boos other amps tend to wash over. You can't fool this amp. With a Line6 modeler in "rectifyer" or "insane" setting, with the noisegate activated, you can pretty much hack your way through anything, and still sound "impressive". But if your left hand is just pressing down on the strings without working on the tone, and your right hand is only busy picking away, that's what the Univalve has to work with, and it won't necessarily make it sound like much. However, this clarity is very helpful as you start shaping your sound with your fingers. There is no chanel switching, to gain boost, no complicated EQ stuff, not even a reverb to thicken your sound artificially. This throws you back to your playing skills and ends up helping you become an individual! Suddenly you understand why a guitar amp can be nothing less than a musical instrument, how it can sing and breathe and react in all kinds of exciting ways to you and your instrument. It's challenging at times, but so worth your while! The Univalve will help you develop into a musician with a personal sound, not only because of its tube switching capacities, but also because it is so honest about what you do when you play!
I must have spent three times the Univalve's price on effect units and other gadgets over the years, trying to make inferior amps sound like this. With just the guitar plugged in, you don't feel the need for any of them. Day by day, I have eliminated the following effects from my chain: a Hughes & Kettner Tube Factor (a great pedal that makes even solid state amps sound "valvy", but obsolete here, unless you want to be able to switch to more distortion while plugged into the "Roll" input), a vintage Tube Screamer (no need! Who knew?), even a Boss RV6 reverb unit (for some reason, you don't miss reverb with the Uni.) and a nice old Ibanez Chorus (what for? It just blurs the exciting clarity of the tone, making it seem less real). All I left in there was my trashy little Danelectro Tuna Melt Tremolo, which seems to turn the Uni into an old Fender amp at times, and an Ernie Ball Volume Pedal which helps me adjust the degree of distortion and find the sweet spot while playing. I have a Mesa cabinet with a Black Shadow speaker which I thought sounded lovely, but then I hooked the Uni up to this 1967 Marshall cabinet some fool left in our practice room, equipped with Greenbacks of course. Oh my god. The clarity, the headroom, the punch.

Finally, a word about guitars. If your amp makes all your instruments sound more or less alike, the Uni is going to make you fall in love with each one of them all over again. I've never heard an amp "understand" a guitar's character like this! Even th

Bought new in Australia for $1400, not cheap but nothing here in OZ is!!!!! Think you all know the features by now, serial #1178

I had no idea what to expect from this amp as we dont have a dealership anywhere near by, just bought it based upon several reviews in guitar mags and here on H/C. I`m using a warmoth tele custom with a hotrails in the bridge, a 2x12 cab loaded with celestion vintage 30`s. I play mostly hard rock/blues, this amp is almost perfect for this style of music as far as i`m concerned. It`s only 15watts sure but has plenty of volume to keep up with a band, the only issue you may have is a lack of clean headroom at high volumes. I`m using EH 12ax7 preamp tubes and an old RCA 6v6, boy does this thing scream with the 6v6, i love el34`s and have been using a svetlana el34 with great results also. Can get a great AC/DC back in black album tone easily so id be pretty stoked if thats all it did. The clean sounds are also nice and you could just about swear that it has a built in reverb, sounds very 3d. Have read some reviews below about this amp being bright but i havent had an issue with this at all, i`m just running most of the tone controls around 1/2 way and the volume at 11 o`clock on the rock input, using the volume on the guitar to clean it up when needed. I love this amp and would buy one immediately if it were stolen or lost. It`s perfect for my style of playing but thats not to say it`s for everyone

This amp seems very well constructed, i have only had it 2 months and no problems so far, from all accounts the people at THD are very helpfull.

I have been playing for 17 yrs, like most of you have tried every amp under the sun, I have owned DSL and TSL marshalls, Boogie dual recto`s, line 6 and a few others. This is the most satisfied i have ever been with my tone, I`m not knocking mesa or marshall as they have great products but THD have something special here. If your into full on metal or just a great clean sound you`d probably be best to try something else but the univalve can cover quite a bit of ground with all the different valve options and do it damn well

Serial #0280. Sat at the shop I bought it at for quite a while...probably a couple of years old by now...I've had it for a year or so. If you don't know the features by now you need to get out more often! It will take boxes and control fiddling if you use it live. I (like most reviewers here)wish there was some channel/gain switching. It won't do Hendrix or Dime Bag (RIP) but with boxes you can make it squeal like a stuck pig! The Roll (low gain) input is for mellow stuff...works fine for the player with the right touch(not me).

I hated this amp to begin with! It took a lot of tubes and cabinets to find the right tone. It's a little bit noisy up loud (input slammed)& is real picky about pedals. I use an old tube screamer into a Boss DS-1 (to add more gain and roll off treble for some lead stuff). This is a BRIGHT amp. Did I say bright? My settings :( clock settings...no numbers) vol. 2 / treble. 10 / bass & attitude at 1 or 2. I can't stand the sound through anything but a 412, but others have used it and loved it in my studio with just about everything. I run a 4 ohm cab thru the 8/16 setting - sounds way better this way to me. Comes across a little noisy the way I play it and feeds real bad if I'm close enough to hear it over the drums...but exactly what you would expect with a little amp cranked like this! I've used everything you could imagine for tubes...I'm the guy listed in Myles' site as the 'unknown' sponsor for Roby with all the NOS tubes (he forgot my name...it's Don?hi Myles?LOL http://www.guitaramplifierblueprinting.com/clinic3.html). I had my Univalve there too. Right now I've got a Sovtek 6550 WA with a very old RCA 12ax7 for input and an old Sylvania 12ax7 for driver. Loved an old Mullard 12ax7 at the input stage too. An old Sylvania 12at7 cleans it up nicly if you're that kind of player. Everybody is blown away by the sound, but I'm soon to try a Flexi for the needed volume & crunch. Players used to an old Fender Deluxe type of sound love it in my studio, but the Marshall guys don't. It certainly has it?s own unique mid range sound. Like Myles says: it's great as a pre-amp for old clean tube amps. I have to admit that I was ready to give up on this until I finally found the combo that I liked. If you've been used to old tube amps this will take some getting used to and a whole lot of testing, but I've decided to keep it now. Obviously I like lots of gain (UFO/Humble Pie/Deep Purple/Montrose/Sabbath/Gallagher) but I don?t want to lose too much more of my hearing!
I?ve been around for way too many years and have tried it all. This thing is a good sounding little amp. Even an old head-banger like me can find a tone if they try hard enough! By itself, you better have 2-412 cabs if you want to be heard without a PA, if you like to crunch like me. In the studio players way better than me love it. If you suck, this amp will show it up better than most. It's improved my playing...enough said.

This thing died on day 2...I was very unhappy. It got delayed in getting back from THD, but they were cool...no complaints. It's hard to blame them for a bad cap...they use the best stuff in this amp. I don't think it will ever need a shop again. I'd bet on it. Built like a freakin' tank. You'd have to prove it to me before I'd believe anybody could build something to better standards. Period.

Ed will talk to you and answer your e-mails. I've been dealing with people in this business since the 70's, these guys are the real deal, you'll never find better! They did a xformer fix for free while it was there (remember, mine is kinda' old...new ones won't need this, I didn't think mine did either, but they didn't charge). I'd give them an 11 if I could. I called on a Saturday and talked to Andy's wife...like I said before, these people are the REAL DEAL. We'd have world peace if everybody acted like them.

I?ve played through Mesa combos (hate them) and lots of old Fender amps. I went half deaf with a Boogie combo slaved to a Boogie M180 power amp in a rack rig, I have a 1958 410 tweed bassman (the real thing!)and the basket case tremolux shown on Myles' site. I'd buy a Flexi if my uni was stolen, but I'm glad to have it. You could buy 6 of these for the price of some of my rigs...nothing out there will touch what it does for twice the price. No, it ain't a Marshall...get a Flexi if you need(I'm going to).

WOW! This amp can do just about anything. I bought this head off ebay second hand. The guy I bought it from owned it for one month. He was looking for that chugga chugga sound. This amp does not produce that kind of distortion. However, the distortion that you can get out of this head is amazing. I can get that early Marshall tone along with the Stevie Ray Vaughn blues tone that I love.

The options on this amp are amazing. So many choices and the tube switching that you can do makes this amp a blast to mess around with. Be prepared to get addicted to tubes after you buy this amp. I have spent a lot of money on tubes and it has been money well spent. You will be amazed at how versitile this head is with just the simple switch of a tube.

The built in attenuator is such a cool feature. Especially when you are playing at home. You can still get great overdrive at a reasonable volume.

This is the best sounding head that I have ever owned. I have been playing for 25 years now and I was skeptical at first but I am a believer now. I am having so much fun with this amp.

Here is a quick description of what I am using. A fender double fat; a 59 strat; and a Gibson 335. I am using the THD Univalve along with my JDesign 2x10 cabinet (2 10' webers). Check out www.jdesigncabs.com for the best custom built cabs on the market today. Speak to Jeff Earl and he will set you up. This is a great combo. The THD through the 2x10 puts me into tone heaven.

Here are the best tubes that I have found. Tung Sol 5881 for that beautiful blues tone; RCA 6V6GTA; and the NOS EL34 Siemens (awesome sounds) Choose your tubes wisely. Be prepared to spend a little bit of money. I am a believer in NOS Tubes. Check out www.kcanostubes.com; www.tubedepot.com; and www.thetubeshop.com. All three of these companies carry some great stuff. You can also get some great deals on Ebay.

For the preamp tubes I am using the GE 12AX7; 12AU7 and the 12AT7. I am also using telefunken. Great preamp tubes.

The coolest thing about this amp is all of the variation of tubes that you can use. You will spend hours looking for amazing tones and when you finally find that great combo it will blow you away.

My favorite so far; NOS Tung Sol 5881; A Telefunken ECC82 and a Tunsgram ECC81. Great tone.

Make sure you check out www.jdesigncabs.com You will not be sorry. I was blown away by the quality; craftmenship and tone of this cab.

Solid Head! I had a case built for it. This is just to great of a head not to protect. I am out on the road a lot so I need to take care of this baby. She found a nice home.

Haven't had to contact them yet. I have heard great things.

If this head were to get stolen or destroyed somehow I wouldn't hesitate to buy another one. This will be a classic in the years to come. If you love music and great tone than run out and get one of these heads. 15 Watts is plenty of power. I play gigs that require a lot of sound and this little 15 Watt head puts out enough tone to stand out in the mix. Do yourself and favor and buy one of these heads.

Number 1287. Traded a guitar for it at guitar center...used..hated the guitar anyway..so hey, it's a deal! Love the simplicity of this..that's the best feature i've ever seen in an amp. The tube switching possibilities are endless. i'm happy with the stock groovetube 6l6. I also purchased an EH6V6 and run it at 5 watts...still kicks ass.

Guitars: 83 MIJ Strat, 77 Electra WorkingMan X290, and 79 Epiphone Genesis. All guitars stock and saved from pawn shops. Amp goes ANYWHERE i want it to. Sound is anything i want or can think of...even that thin crispy critter 60's beach sound if wanted. Would love to try a 34 or 6550 in it. I don't find it too noisy...it's a REAL amp. Hey, just for THD, harmony central should put this number up to like 20 for this rating.

So far so good!

This is almost a given that they will be great to deal with. If someone can create an amp that sounds like this and put the "love" into like they do, do you think they'd suck at customer service? NO! I bet THD guys love to help you and talk about their products. They have to be very proud of it so why not!

You know..this is very subjective. Some "kids" may not ever appreciate this amp. They didn't grow up hearing "real" amps in their sleep. I'm 39, playing since i was 10, youngest of 7 and with older bro's and sis's, i've heard lots and lots of music over time. Solid state was not what was on the radio growing up. now you hear nothing but modeling amps and "close" sounds but nothing like the real thing. So kids today "think" that line6 models are faithful. I've played EVERYTHING imaginable in amps...solid state, tube, hybrids with tube pre-s, hybrids with tube power. and YES, i'll confess i was getting close to really liking the valvetronix vox ( a very respectable hybrid amp by the way) It's a sad truth though that there are a lot of kids playing who have never heard or played through a real amp because they are told by the stores that "models" are just as good. well in the case of thd's univalve, it's as versitile as any modeling amp..but the thing you feel in your heart and soul when you play it that it's real...it's not a model and your life will be much better having it around. Thanks THD for rescuing me and all the rest from being buried in the crap that's on the market...thanks for letting our sound climb back on top and even if i don't make another dime playing, every time i plug into my univalve, you'll know i'm smiling!

Single output tube class A head with attenuator and direct/line out. Two inputs voiced differently.

No effects loop. No onboard effects. No channel switching.

Great clean to crunch sounds especially with 1 x 12 Jensen PN 12 or Celestion Blue. The Roll input with 2 ECC83's in the preamp and a JJ/Tesla blue EL 34 yields glassy clean sounds with Strats and Teles.

I have an old Magnavox 6V6 tube that I pulled from an 1950's record player that sounds absolutely killer with an ES-335 thru the Rock input.

Overall, this little amp is like a science lab for tube enthusiasts. Its fun to explore the subtle differences among various preamp and power valves.

You can make this amp sound fizzy and ugly if you use the attenuator too much with certain valves. In general though, it is fairly easy to dial in great tone. I love the clean sounds that this amp does thru the Roll input.

Looks pretty solid.

I have emailed them for information about other products and have gotten prompt and courteous replies from Andy Marshall.

I have collected all kinds of guitars and amps in my 38 years of playing. Guitar playing is my lifelong passion, and I don't skimp or compromise when purchasing guitars, amps, and effects. I own 3 Les Pauls, an ES-335, 2 Strats, a 52 Tele reissue, 4 Rickenbackers, and a CIJ Jazzmaster (my only import). I perform through a Vox AC-15 TBX and a Marshall JCM 2000 DSL most of the time, but my beloved Vox is getting pretty beat up, so I decided to replace it with the Univalve and a cab. It sounds as good as the AC-15 TBX for clean to medium gain sounds. I still carry the Marshall to gigs when serious drive is needed.

I really like this amp. I have had it for about 6 weeks, and I am still working with various valve combinations and different speakers. It pushes my 4 x 12 easily, and has more clean headroom than you might think. But if REALLY LOUD AND CLEAN is your thing, look at the BiValve or the Flexi.

Here's a link to a photo of some of my gear:-)

http://www.coe.unco.edu/jeffbauer/group2.jpg

I give it a ten because even though the number of knobs is limited, it will get any sound I want, from sweet and clean through sweet and singing to as raunchy as I want. No channel selecting is provided, but I change the tone in real time as I play using a volume pedal to provide the desired amount of overdrive.

I've used it with a variety of Gibson and Fender guitars and all styles. It gets beautiful, diverse sounds with all of them. Using an ES175, I can sustain any note as long as I want and bring in beautiful feedback harmonics an octave or two above the note I'm playing, at will. Fantastic. And the built-in Hot Plate is the "master volume" control I've always wanted: It controls the final loudness without affecting the tone, so I finally get as much singing or crunching or wailing as I want at a volume suitable for a modest-sized practice room. I have concluded that the people who complain about its tone just don't know how to use tone controls.

I've had it only a few months, but it seems very solid. It has only three tubes, and they are easily replaced. So, I would not bring a backup amp--just spare tubes, in case they are needed.

This is based on wishful thinking and hoping. I've never needed to call them, but they have a great reputation. I often think of calling them just to tell them how much I love this amp.

I've been playing about (gulp) 40 years. I have tons of guitars and amps. This is my current favorite. I could probably ditch all the other amps and be very happy with just this one. There's nothing like real power tube distortion, and this provides it at comfortable loudness levels. The only thing I would change is to have protection for the knobs, so they don't get broken when taking the amp to another location. This has not been a problem because I keep the amp at home, but they do look vulnerable sticking out there. Maybe a custom road case should be offered (cheap!).

serial 1233.... i have tried ab'z of later model... (silver thd logo) white thd logo and found that one (marginally) thinner (despite substituting my valves) .. perhaps it was that amp only....
Loud as my 50W JMP-Mk11!!!!
Try rca 6v6's...dual getter mullard el 34s....

63 Duo
62 Duo...freak (custom order) paperweight swamp ash xtra factory winds, steel klusons... this is a gem!!!
92 Carruthers handbuilt strat... swamp ash/ antiquities.

amp has a fair bit of noise, but the tone is a killer... from blues to rock to jazz to anything.. the preamp stage is a gem, albeit not for novice dialing.
Yhe secret .. as with all valve amps is to use micro adjustments... Want darker? Dial more gain... realise that this ofcourse affects all the followint tone stages.. adjust!!... remmember micro adjustments... if you use this method you can focus any guitar just yummy!
There are some cool sounds using the noise reduction and attenuator (not too much of it) ..BUT!!! the tone really lives when you let the power amp breathe... so you are better off getting lower output valves...
I use my marshall quad...original greenbacks.... tight cool ...great bottoms...well everything....from brit shimmer (it is class A after all...)
I use 2 vintage screamers and a quadreverb gt .. this for reverb only... what can i say? this combo is sublime to delicious...
Clean shimmering tops , bottom end to spare, and the mids are there if youhave the knowhow to fucus them... just use fine touch not brutal knob turning...

very cool amp.. built with attention to detail.

over and above and beyond service at its best!!!!

a future clasic!

At first I was a little nervous purchasing this amp because i am used to using channel switching amps that have many knobs that do many different thing. i have used Mesa/boogie amps for many years but have always had volume issues at gigs and with other bandmates. the operation of the amp is very simple and very no-frills. I have read reviews on here where people have complained about the price and i find that a bit odd. if you compare it to other class A amps out there, it is very reasonably priced.

I am mainly a hard rock/blues player. I use a 61 reissue gibson sg with a dimarzio tone zone pick up in the bridge. i have been running it through a mxr micro amp (just to boost the signal for lead work) and then right in to the rock input. it took a little while adjusting to the old school method of rolling back the volume knob on the guitar for clean sounds, but is no problem now. for me the amp is plenty lound for small to medium size gigs. I have been using it at all gigs because it always gets mic'd up and run through the PA anyways. I may run it into my mesa on larger stages, just because I can.

I have experimented with a few different tubes and found the sound of a 6L6 works the best for me, its a little warmer sounding than the el34. I tried a 6v6 in it and found the sound to be amazing but I have my doubts that it will be loud enough on stage.

the only complaint I have in regards to sound is that the treble can be hard to control, and can get a little piercing at times.

no problems so far

havent had to deal with customer support, but univalve.net is a great resource for this amp.

I think this is a great little amp. fun for experimenting. I think sounds best being used for clean to hard rock sounds, not enough gain for metal. if you love great guitar sounds in the realm of ac/dc, aerosmith and guns n roses, this is a great amp

-Dual independant inputs for clean or dirt
-Built in power attenuator (hotplate)
-selectable impedance speaker out (use any cab in your collection)
-Line out w/ volume control
-Noise reduction circuit (simple yet effective)
-AUTO BIAS circuitry (swap pre or power amp tubes to taste)
-Bass, Treble and Attitude (how hard you drive the power tube)
-Low/high voltage selector switch

That's a lot of features for a little 15watt tube amp!

Sounds fantastic. The amp is not a modeling - it won't go from blackface to soldano tones at the flip of the switch (or swap of a tube). It can go from a Fender-ish sound to a Marshall-esc sound fairly easily though. For higher output crunch tones try using a pair of 12AX7's and an EL34 in high-voltage mode. For more Fender Deluxe type tones try a 12AT7/12AU7 and a nice 6V6 in low-voltage mode. Either way - whatever your prefence it sounds good.
I was just in the studio with several really nice amp and the THD. The Univalve is no slouch in the studio and ended up being my go to amp despite being in a room with a vintage Plexi, a vox, a deluxe reverb, a matchless....you get the picture. I wouldn't say the THD sounded "better" than any of the other amps - it sounded comparable and for what I was doing it worked better in the studio. My Uni really shines with a telecaster, plenty of nice tones from a Les Paul too but the chimey quality of a single coil is very pronounced through the Uni. This isn't an amp for rookies - if you want crazy flexibility go get yourself a Line6 amp - or a Zoom! If you are familiar with quality amps and would like a solid 15watter in your collection this is a great amp a very reasonable price.

I've owned my Univalve for about 8 months. I practice with it a couple times a week, I gig with it regularly, I use it in the studio. It's never given me any trouble at all. I've swapped tubes many, many times and never had a problem. I don't suspect I ever will either - the design and build of this amp is top notch.

Haven't had to deal with support at all - but there is an on-line bulletin board run by fans of the univalve and a few THD employees are frequent contributors. They are very knowledgeable and very cool about answering questions.

Been playing since the late 80's and own many guitars and amplifiers. Most of my amps are Fenders which is sort of why I bought a THD this time out. I wanted something that had a great clean sound (that wasn't the fender clean sound) and had a nice tube distortion. I decided on the Univalve because it sounded great, cost about 1/3 the price of other boutique 15watters, and had so many cool - useful features. I would buy another if stolen. heck I might buy another just because they're too damn cool.

Hotplate, great line out, loud 15 watts

Sounds good clean, but I though channel two should be called "clean 2". Maybe I'm too modern, but that's how I feel on the distortion. It's too damn noisy. I have to keep the controls less than half way up. I use a Gibson LP.. The hotplate is a piece of shit. Talk about fake! The thing makes your dynamics flabby and timing off. It's like an old computer...you can notice it takes longer to respond. The notes seem to have a delay. I tried other tubes but I don't care for those either. People have mentioned it has that hi-end fizzle or buzz sound...That's not part of the sound it's the freaking white noise.
I got this at musicians friend and they got it back 2 weeks later.

Built like a rock... I know why. Cause you feel like you want to beat the hell out of it because it's an annoying amp. The controls and such are a pain in the ass.

Who cares.. never tried nor needed to.

Clean with controls never over half way = great clean amp.
Distortion? hah.

I bought mine new about 4 weeks ago.

I like both Heavey Rock, Metal and Blues.

You can change the two input tubes and the Main Power Tube, and mold the tone to your liking

It has a high voltage and low voltage switch that does change the tone.

It has a builit in attenuator to cut the volume. The more you use it, the more it effects the tone, but using about 1/4 attenuation cuts the volume and only causes the overal sound to suffer a little.

For 15 Watts, this thing can be very loud in either high or low voltage.

Like all tube amps it sounds best cranked.

I've tried a number of different tubes in it, and changing the tubes really does change the character of the amp.

Not all tube combinations sound good, but I have found five our six that really sound quite good.

My favorite combo is 2 12ax7's in the pre-amp, and a KT66 in the Main slot.

This is one of the best built amps I have ever touched. It reeks of quality.

I am giving it an 8, not a 10, because it lacks channel switching and built in reverb. It is a 10 in all other respects.

It has a line out, a hot plate, noise reduction, and two imputs.

What it has is 10 quality, but this is the "features" section.

I use an ESP with stock PUs. A fender Strat, a Charvel with a SD super distortion, and an Epi LP.

It sounds best to me through the ESP.

Guitar selection and pickups make a huge difference.

My brother has played an Ibanez with Dimarzio's through it, and an old Samick with Tone Bone's in it.

It sounds different with each guitar.

One of the nicest features is that it really reacts to the volume control on the guitar. You can find a sweet spot where if you pick softly, the notes are clean, and the more you bear down, the more distorted they become. This works well in solos stuff and hitting the same chord with increasing amounts of force.

Here's the deal about overall sound, pay attention.

This is not a JCM800 or a Triple Rectifier. With pedals, you can get both tones, or pretty close.

THIS IS THE BEST SOUNDING DRY AMP I HAVE EVER PLAYED. There is a certain warmth and character to it, that defies explanation. It breathes and reacts to how you play it.

The only people that I think would play this and not love it are guys looking for level 11 distortion.

It will do a dead on AC/DC marshally crunch sound that sounds better than the record. It can give you a nice crunch "Pat Benetar" "Heart" type crunchy rythym sound.

With some effects, you can get a pretty sweet "Scorpions" tone out of it.



You are going to have to drive it with something if you want blistering paint peeling distortion leads (as is required of all amps)

Other than that, I can't imaging anyone wouldn't like this amp.

THD has sound clips up on their web site. I don't think they do justice to this little amp for the heavier stuff as most of them are oriented around a nice jazzy, bluesy type sound.

The sound is very "thick" and 3d as everyone mentions.

Some people have reported that it is "tinny" or high on the treble side, but I have not found it to be.

I understand that the cabinet choice makes a huge difference.

I have played it through a Peavey 4x cab, a Marshall 4x with vintage 30's and used the line out into a power amp and out to a pair of fender 2x12's and it sounded good through all of them.

This is not a magic carpet, it does not do one and only sound and do it well. It is a multi faceted tone machine, that you will have to tweak.

Quit plugging into amps dry down at guitar center and wondering why it doesn't sound like a record. Put some effects on it, mic it, run it into a board, throw some compresson, e.q., reverb and delay on it, and maybe an overdrive pedal, and come back and tell me this isn't a studio quality rig.

DID I SAY THIS IS ONE OF THE BEST SOUNDING AMPS I HAVE EVER PLAYED.

I got mine from Music Toys for 699.00 and think it gives you some of the best bang for the buck of any amp PERIOD.

Go buy a $3000.00 bogner and I will buy a 700.00 amp and spend the other 2700.00 on effects, and kick your ass.

It lacks channel switching and reverb, but for the price is the perfect "base" for building on it.

You will notice if you pay attention, that a lot of guys who have bought the amp have 20+ years of experience and give it high praise.

Don't take the word of some kid with a Metal Zone pedal that this amp won't get nasty, who has never played a real Marshall, Rectifier, or Botique Amp.

Is this the best amp in the whole world...maybe not.

Is this the only amp I would ever want, no.

Will I ever buy another amp...sure.

But this is one of the best values for the money and sounds very good for most styles of playing.

Once you figure out that you can get different tones with different tubes, it becomse even better, because it isn't a "one tone wonder".

I bought mine off the internet without ever playing one based upon the good recomendations they recieved.

I have not been disappointed.

I have tried a number of distortion pedals and stomp boxes through it, and it takes to them very well.


I give it a 9 as I hardly give anything a 10. For the sound

Only had it a month. It's easy to change tubes.

THD...they are a 10.

They will answer your phone calls and e-mails immediately.

This thing is a 10 overall. I don't know of a single amp in this price range that sounds as good, has as many features, and can be put to so much varying use.

I think this is a 2004 version, because I bought it new. Very versatile, the hotplate and noisegate are a big plus. Two channels Rock for crunch, Roll for clean and blues. I use all the features depending on what kind of sound I am recording. I use this amp at home for recording, plenty of power for that application.

I use a Brina Moore i2.13 "seymour duncans", a Ibanez 540 pII "Ibanez F2 and F3 humbuckers. A Explorer "gibson paf's". This amp suits my style "Rock/Fusion/Jazz". Only noisy when amp is flat out cranked. I can get the real crunch chords sounding great on all three guitars. The clean sound is transparent warm and glassy. The clean channel can be overdriven for bluesy type sounds. The distortion seems to self adjust to whatever guitar or pickups you feed into it.

I have only had it week, I have taken note of fuse consideration's from the posts here. I will order extra sets in case they ever blow. Amp seems to be built very solidly. I have'nt gotten into changing tubes and the such yet. So I will give this a No Opinion.

I have called Ed Degenaro "THD" twice and he was very helpfull. He also pointed me to the univalve.net chat room, alot can be learned about this amp there. I am not sure about the warranty, no manual was included.

I have been playing for over twenty years. I run this amp into a Randall 12" celestion vintage 30 isolation cab, miked with a AKG C3000B condensor mic. That signal goes to my yamaha mixer, then my M-Audio breakout box, into Cubase 5.1 PC recording software. I was trying to get a tube sound into my recordings, and this system does the trick. I got tired of my POD sounding so digital and harsh. I chose the THD because the hotplate was already in it. I considered a Soldano Avenger, but I didn't need that much power for recording and I would have had to buy the hotplate extra.

Read the other reviews: I agree with them - very versatile and has effectively a 'virtual reverb' as it sounds 3-dimmensional !

Tubey, Jazzy, Bluesy, Sweet, Expressive, Incredible, Soulfull, Punchy, Rocky, Singing, Growling, Melting, Holy, Divine ...

These are the comments from my audience and my band members. They actually told me that I sound like Jimmy Hendrix or John Abercrombie or Buddy Guy or Wes Montgomery ... and I am not that good but with this amp I do sound that good :-)

Just buy one, period.

excellent

I play since 1964 and have played many amps and guitars and this is the best, period. So, like what the other people wrote already as it summs it best; quote: ''Andy Marshall, CEO and key designer of THD is ''boutique amps maker boutique amp builder'' so simply put, once you get a Univalve, or Bivalve, you won't care about the competition.''

I no longer search for another amp and concentrate on my playing.

You know the deal: Controls for Treble, Bass, Attitude... Hot Plate Attenuator, Rock (distorted) and Roll (clean) inputs, Hi-V / Lo-V, speaker load selection, I could go on, but I'm sure you know about the amp's basics.

Wow.... what an amp! I, like you are doing right now, read reviews on here, and was blown away by what people thought about this amp.

The clean is sparkly and has a certain depth to it that I love. I miss the reverb a little bit, but hey, you learn to live without it. When cranked, the Roll 'channel' dirties up BEAUTIFULLY... awesome with a humbucker, or higher output bridge p'up.

The Rock Input - absolutely beastly! Will tear your face off if you want it to. This may be a 15-watt amp, but it rivals many much higher powered amps. Does Guns and Roses awesomely, Alice in Chains, you name it.

Many tube amps are one-trick dogs... this little guy does it all.

Can't comment much, have only had it a week... but looks like it's built like a brick shithouse.

Well, Ed is an awesome guy, and THD is a top-notch company... but I can't give a perfect 10... I ordered the amp in early, early February and was told I'd have it in two weeks. I called in two weeks, and was then told it would be shipped out the next few days, and I would be given a tracking number... 4 days went by, I called again, and was told 2-3 more weeks... It finally came in mid March, but I guess I shouldn't be complaining. Too good an amp to be picky.

Awesome, awesome, awesome... take my word for it.

See the reviews before me...no sense reinventing the wheel. I play at home and it's PERFECT for me. The best part is that you can change tubes and you can get a different sound with each tube change. Very versatile and VERY LOUD for a 15 watt amp. The only thing that I wish it had is a way to switch between the Roll input and the Rock input.

You can go from a super squeaky clean to full on metal. Now, don't expect the clean to be as loud as the distortion, because it's not going to be. TUbe selection plays a BIG part here - a 6550 will have a lot more clean headroom than say a 6W6 or 6V6. Plus, if you use a lower gain preamp tube in the driver slot - say an ECC81 or 82, the clean will get a bit louder before the amp starts to break up. Break up - ahhhh - the BEST part of this amp. You can get MELTDOWN power tube distortion and have it so that you can hear the TV over the amp. The Hot Plate adds a complete new palette of sonic options to an already full plate of tone. One thing though, if you turn the Hot Plate all the way down the sound gets a bit thin.

Built like a tank!! The guys @ THD really have their act together!! Top notch build quality - some of the other amp manufacturers could take some pointers from them. One thing - get extra fuses for it. I had a tube short out and blow the HT fuse. I had quite a time trying to get a replacement. I contacted Ed @ THD and he sent me replacement fuses!! You could gig it without a backup...just take extra fuses and tubes.

One word - EXEMPLARY!!

Awesome amp. I should've bought this a LONG time ago - I would've saved myself a lot of money AND grief. I would highly recommend this amp to anyone.


P.S. - on a side note - Avatar Speakers has the best price on the web for these amps. www.avatarspeakers.com

As described before.

I just want to add a few comments after the previous, evidently British, reviewer who apparently tries to be objective but isn't, or at least misses the point ...

I did own #499 6W Cornford Harlequin and can first hand confirm that it sounded unfortunately VERY BOXY and had 50Hz hum even though it's a recording amp ... as to the Hurricane - yes it's nice but then the price is #1200+ and still you have a limited range ... for $1800 anybody can build a decent tube amp!

In short the reviewer did not have the right cabinet for THD amp.

I get any sound you can possibly imagine simply by using a DEEP (rather bassy) 112 cabinet; alternatively try THD 212 or any decent 412 ... so do not grumble if your cabinet is lousy ...

In short this is THE best amp there is (especially for the money) but you have to choose the right tubes and the correct cabinet.

What to say - perfect

Great guys at THD !
Great user forum too !

Perfect. You can get any Cornford or Dr.Z or Dumble or Bruno or Kendrick or Fargen or ... whatever boutique amp you dream: yes Engl and Randal and Koch and Zorotoustra too ...

The secret is simple, as Groove Tubes owner said:

''Andy Marshall, CEO and key designer of THD is ''boutique amps maker boutique amp builder'' so simply put, once you get a Univalve, or Bivalve, you won't care about the competition.''

Just go and buy one with a decent cabinet and do not worry about anonymous comments - the only almost as good an amp made in Britain is anyway class A #699 Matlab V28 (ask Nick Guppy ... from 'Guitarist' if you do not believe me :-).

Mine was a 2003 model. You know the features: cool styling, Class A, rock and roll inputs, atenuator, can used different preamp and power amp tubes. It's a great little package, ideal for the studio but still way too loud for home use. No effects loop (not a criticism).

I wanted an amp for home and studio use. I considered the Harlequin also but was attracted by the THD company ethic, the glowng reviews, and the flexibility offered by the valve switching.

I really really wanted to like this amp. Clean it sounds beautiful. The sound is 3 dimensional and airy. It's wonderful, especially on the roll input.

The problems for me started with distorted amp sounds. I like to play classic blues through to heavy rock/metal. Without the attenuator 15 watts is incredibly loud. I couldn't get a really nice distortion without the treble hurting my (and my wife's) ears. I tried different valves (including NOS), different amp settings but couldn't get it right. Plus using the attenuator robs the amp of its ability to accurately reproduce the power stage distortion (I know the attenuator works post-power amp). As with all classic valve amps, volume is needed for great tone. Maybe I just didn't match my needs with the amp right. But I still don't like the brightness (which is acknowledged by a lot of univalve owners - check out the univalve forum - a great forum BTW).

I tried using distortion and overdrives on the roll input but it just didn't sound right. So I sold it and bought the Harlequin which for my needs was great.

I would submit that the amp sounds great clean but not so good distorted (at least for my needs). My score attempts to recognise this. If you're thinking about buying one, test it well and make sure you know what you want and make sure you like bright sounding amps.

I suspect it would be a long lived bit of kit treated right but probably wouldn't stand up too well to the road. Most problems would I suspect be tube related.

No experience of customer service. However if you get one, the univalve forum is great and a number of the guys from THD are members and respond very well to queries.

This is a tough one. It certainly is a unique amp with superb flexibility and design. If you want mainly clean/crunch sounds I think it's a good one to audition. If you want classic/hard rock think hard unless you like lots of treble. If you want nu-metal you're on the wrong page anyway!

I/'ve own/ed Mesa Boogie F50, single rectifier; Cornford Mk50, Harlequin, and Hurricane; Marshall DSL50 valve amps. I think I know a good amp when I hear one. I play PRS, Tom Anderson, Ibanez, Gibson and Taylor guitars. The THD is a good amp for some purposes. If you want a valve amp for studio/home use also check out the Cornford Harlequin.

Versatile studio amp. It would be nice if there were a way to equalize the high and low inputs and switch between them to get high gain and clean on the fly. All of the features on the amp work well and it is very simple to operate

Flat out one of the best sounding amps I have ever played. Sounds great through a variety of speakers. My favorites so far have been a pair of Weber Blue Dogs in an open back cab and a pair of Greenbacks in a closed back cab. I can get country, jazz, blues, hard rock and early eighties metal style tones. It is what it is and does not sound "exactly" like a given amp, but it gets in the neighborhood of many great classic tones, all while putting out a fantastic sound of its own. I have played it with many guitars, including PRS, Gibson, Fender and all shine through it. Playing with various tubes is fun and this is where you can find the tones you need. Sounds so good I decided to get a BiValve to have similar tones but with a little more clean headroom when gigging.

I have gigged with it without any problems. I've had it for over a year and it is still going strong.

Ed DeGenero is a model of customer service. He hangs out at the univalve forum and is very willing to answer any questions. I've yet to see better customer service from any other company. The only manufacturers who have compared when I needed them were: PRS, Mesa Boogie and Fuchs Audio Technology.

I have been playing for over 20 years and have been through a ridiculous amount of gear. This amp kicks butt and if it were stolen I would probably replace it (If I didn't have a BiValve on the way, that would be a definate).

As stated throughout these reviews, the amp's features are in service of getting the right tone at any volume, hence the built-in hot-plate. My favorite stuff is on the backside: the line-out feature works extremely well as either a line or instrument level output to another amp, modelling device a la POD or hard disk recorder. THD has also demystified the art of re-tubing and rebiasing. In fact it is an enjoyable task, as one hears and appreciates the potentially dramatic results in tone. In this category, I'm celebrating the effectiveness of the features that are included, as opposed to lamenting what's excluded --reverb, effects loop, et al.

I've use a variety of guitars. Including my main Les Paul Standard, I play Dano Baritone and 12-String models, Standard Tele, Line6 Variax (sounds great with the Uni), and a modified Epi Sheraton.

After a month of heavy use, I'm confident that is amp is, if not the best value out there, a fantastic specimen of a low wattage amp. The tone is pure manna from Class A heaven. I've owned an blue alnico equipped AC30, and as much as I loved the full throttle tone of that particular amp, it was difficult to acheieve desired results with anything less than rafter-shaking volume.

The Univalve excels at providing a great crunch that cleans up very well with the turn of the Guitar's volume knob. I've read some players lammenting the lack of a clean tone; however, I'm satisfied to run the amp wide open on the "Rock" channel for maximum wattage and adjust the volume on my guitar accordingly. I recognize this isn't acceptable to some players seeking more versatility, but with tone this good, i'm comfortable with limited options.

Concerning the output of the amp, I have had more than enough whallop to compete with drums, bass and another guitarist's AC-30. It should be noted that using a beefy power tube such as a 6550, KT88, or EL34 will create twice the output of, say, those of the EL-34 or 6L6 variety. Cabinents, of course, make a difference. I'm currently using a Laney 4X10, although I hope to upgrade to a THD 2x12 cabinet.

When recording, I've preferred the sound of an EL-84 and a Tung Sol 6L6, as these seem to yeild richer harmonic content. For playing out, I've been most satisfied with a Svetlana 6550 --a great combination with 12AT7 preamp tubes, that has a crushing old-school Hiwatt distortion at high volumes, and austere clean tones at lower volumes, around 3-4 on my trusty Les Paul.

The amp has the heft of quality. This was shipped to me, used, and I haven't experienced any issues with fuse or tube failure.

I joined the Univalve Board. There's some helpful threads, FAQs, etc to give the new user direction and support. It's obvious the designers/engineers care as they weigh-in on a variety of topics relating to their creations.

I have never known or experienced a tube amp that sounded great at any volume, let alone one that could be routed into another amp (via the instrument level, line out) or recording deck with equally impressive results. THD has really given the Univalve the features and tone to have it qualify as a lifetime amp. I'm sure there are great boutique alternatives, alas but how many fall under $1000. Simply put, once you get a Univalve, or Bivalve, you won't care about the competition.

See the specs given by other reviewers.

Before I give any comments here is an advice for all novices:

Choose your tubes and try the amp in the following mode:

All EQ knobs at 11 am and use the 'powerbrake' (not the full power) plus the noise-suppressor ... adjust the volume ...
usually the best is when power is at 11am and gain at 2pm.

The amp will gently sing and when you play softly offer a sweet tube sound that you can usually only dream about ... adjust the knobs a little to suit your style and your guitar and enjoy ...

I now use this amp always in this power-brake mode and adjust the amount of distortion with playing dynamics ... the tone is always perfect - 10 and I mean - ten.

Very reliable.

They always responded to me and advised me ...

Some people prefer BiValve but I have all I need with Univalve.

If I need some reverb I often use my $230 Laney LC-15R 110 as an extra small combo and when I place it next to my Univalve (with 112 cabinet) it acts as a reverb-add-on quasi-stereo amp that projects more as it has 10'' speaker ... nice combination and sufficient power and projection for ANY gig even with very loud drummers ... strongly recommended combination ... probably some other second tube amp with reverb or decent small combo with reverb can do the same trick too ...

I have some really expensive gear yet this THD amp has THE tube sound that serious guitarists dream about ...

If you are searching for THE sound buy one of THD amps ...

This is a well thought out chunk of machinery. I've had it now for about 6 months and every day that I use it, I appreciate it more. The amp works great for practicing downstairs at reasonable volume levels, and yet you can use the Line Out jacks in the back to push it through another power amp.

I am presently using Fender Strat and play a variety of rock / blues styles. The amp sounded great out of the box, but anyone who gets a Uni will start to play around with different tube combinations. They really do sound different, although in all honesty, almost every combination I've tried has sounded great. The built in hot plat is a real added bonus. About the only other effect that I use is a Boss RV-5 reverb box. Although the Uni almost has a reverb sound, I like just a little more (could be the room I practice in). I got my THD 2x 12 cab about a month ago. It sounded crappy for a about a week and now it just sings. There is some truth about speakers needed to be played hard for a while before they sound right. The THD system I have now means that my little Marshall practice amp is gathering dust in the corner.

The way this thing seems to be built, I will be shocked if it ever breaks down.

I've never had to contact THD for anything. From what I've heard they are a great group of people.

I have no hesitation in recommending this unit. After playing through a solid state amp, there is just something magical that a tube amp gives you. When you play through gear like this, the hours just fly by.

As I play since 1960 and have tested almost all top amps on the Planet (yes, from Philips or Selmer, via Vox through Marshall, Fender to Cornford or MatAmp etc ... but also VG-88v2 or VGA-3, Zenterra etc ...) I think I can say: this is THE ultimate dream for ''Woodstock-generation'' guitar-amp jazz-blues-rock players.

Please, do not misinterpret this analogy, yet it describes the essence of this fabulous '''HAREM'-amplifier'', rather well:

Nowadays, you can buy one of these new digital zillion-features sounds emulation-amps (changing mistresses all the time, but with anti-aids protection, it's not quite a 'real thing'), or you can buy this versatile ''harem''-amplifier :

Namely, the Univalve uses a collection ('harem') of the world's finest valves (selected beautiful women in your 'harem').

And it's a REAL valve(s) thing,so if you ocasionally dislike some tones, well, change the valve(s), man :-)

All the rest is secondary in this inspired amplifier design.

It's YOUR CHOICE ! And that's why some people get it wrong.

You can use AX7, ECC83 and 6550a through a vintage 112 Fane cabinet (softer sounding) like myself for jazz , or get slightly more aggressive with EL34EH and 412 marshall cabinet for rock ...

You can add small Danelectro SlapEcho minipedal to mimic 'reverb' or addan analog Ibanez AD99 delay-echo pedal or use any other top OD like Fulltone Fulldrive 2 or Maxon OD808 ...

... and it all sounds fabulous IF you make CORRECT choices.

Do not blame OTHERS for your wrong choices in life (mariage) !

This is definitely THE VERY BEST guitar amplifier soundwise
as if you cannot get some sound it's your fault, not THDs: I repeat you can get any ''Woodstock-generation'' sound ...

Beyond that, i.e. nu-metal or trash or nihilo-rap ... use these new digitalo-computerized aggressive sound generators ... as this amp cannot offer sounds that are of non-valve origin.

Mine was 2nd hand and sent by snail-mail from New York to Switzerland and survived 8 weeks of trans-atlantic travel in probably very strange conditions and still sounds - Divine :-)

Go to www.univalve.net and read - perfect community !

If you have any imagination then you can understand that a guy who begun playing guitar BEFORE the Beatles became a known band, and before Marshall designed even his first cabinet ... did have sufficient time on this Planet to test all the best gear (I am a physicist and I travel around the globe so can and did test virtually any top amp that people mention in these forums) ...

If you are baby-boomer guitarist, the GOOD news is: buy this amplifier, and have peace of mind. Just choose the cabinet and stop worrying about tube sounds as you will have them all : just choose a different guitar and change valves when you need a different texture ... this amp provides all basic options.

Effects you can add later and in my tests I learned that all decent pedals can be easily used with this amp and sound great.

For wild non-tube guitar and other artificial sounds I use in parallel Roland VG-88v2 and GR-33 through Roland VGA-3 or Cube 30 digital units ... but in the tube sound arena this is it.

I have sold all my other tube amps, except for Trace Elliott designed Gibson GA-15RV as it is sweet sounding combo for small jazz-blues gigs (where I need relatively little sonic range).

If it were stollen I would buy it again. And NO I didn't want the BiValve and the reverb as this Univalve provides all the sonic tube basics that sound Divine and is sufficiently loud ... mics exist, right (and yes, I did try Fargen and Dr.Z ... amps too :-)

In summary, if you are baby-boomer guitarist: go and buy one !

"Opinions are like armpits, Everyone has them and some of them stink." I have the good fortune of playing in two different bands. One is blues oriented and the other is country. Until now I have had to have two amps to cover the different styles. A Marshall JTM45 Offset Halfstack (sweeet!) for the blues gig and a '65 re-issue Fender Twin for the county. With the UniValve all I have to do is change out the tubes. The 15W this thing develops is plenty for me. That's why Shure markets the SM57. The only cab this amp sounded just OK with was an old, old Crate 4x12. Everthing else (Mesa, Marshall, KJL, Cruise) sounded outstanding.

I generally bring at least two guitars to every gig. Right now my favorites are a '52 re-issue Fender Tele, a G&L ASAT Classic with a double coil in the neck, a Strat of some sort, and a '58 Les Paul re-issue. Regardless of the guitar I choose this amp sounds awesome. It can be a bit bright so I pull the tone down just a bit on the single coil guitars unless I really need that 12ax7/6L6 spank with the country fellas. Putting a 12at7 in the drive position with a 6550 power tube this thing eats the blues up! If I want rock substitute an EL34. This amp is ideal for pedals like the Diaz Texas Ranger. I finally understand what the late Mr. Diaz was going for. Is this amp going to cover stadium gigs? Not unless they use an iso-cab and feed the signal thru the main PA. You didn't think those 4x12 cabs were for real did you? Bottom line...If you like tube amps you are going to love the UniValve. If you want the death metal drop C thing go for the Marshall Mode Four.

Since I've only had the amp for a while it's kind of hard to say. However, I've yanked more tubes in and out of this thing than a normal person should and the tube sockets haven't shown any sign of getting loose or losing their grip.

The cusomer support is head and shoulders above anything I have experienced before in or out of the music biz. I get replys to my e-mails in a matter of minutes and the phone never rings more than a few times before someone picks up. With all the poor customer support in the superstores lately it makes you wonder if maybe the little guy is the way to go?

I've been playing since '66 and have never had such an exciting sonic experience. I can't wait for the THD 2x12 cab to show up.

I believe my amp was made in 2001, but I got it used in 2002.

This is a very feature loaded amp, offering many features not available with other amps...

One of the most underated aspects of this amp in the reviews here so far is the ability to use its instrument level line-out to make this into a superior PREAMP.

In a live situation where additional volume may be required this use of the UniValve offers a great solution that offers virtually unlimited volume along the great UniValve tone.

Most amps aren't designed with a instrument level out. If you simply plug a line-level out into the input of another amp, you can get nasty results.

Not only does this have the right "instrument level" signal, but it also has a "volume control" for this output which allows you to fully control the signal to a second amp.

I typically use this into the "poweramp in" on my Fender Hot Rod Deluxe, which bypasses the tone stack on the amp. This allows the tone controls on the UniValve to be dominant, and that's a simpler solution for my needs. It still sounds great through the normal amp Input... so you don't need another amp with a specific poweramp in.

Because this input on my HR Deluxe also hits the reverb it has the added benefit of allowing me to use the Fender reverb when I want. Nice.

Another plus is that I can still send a signal from the normal speaker out of the UniValve to any other cabinet I want. So I can easily get more air moving and control the volume to each independently. Nice. I often use a Line6 delay in line with the HR Deluxe, which ends up giving me a "wet" sound from the HR Deluxe and its speaker and a "dry" sound from my other cab, a Carvin 2x12 with Celestion Vintage 30's.

I've got a variety of guitars and play mostly blues, jazz, and classic rock styles. This amp, combined with a nice and growing set of power and preamp tubes gives me a great range of useable tones.

Unlike some reviewers, who seemingly struggle to find sounds they like, I find it hard to find sounds I DON'T like.

Some of my favorites include 6V6's using the hotter "rock" input combined with a nice 12ax7 and a 12at7...

I also love the sound of big tubes like 6550's, KT-88's, and KT-66's using the same preamp tubes. The more powerful tubes provide plenty of power for the "roll" channel, and I get a great clean-on-the-verge-of-breaking-up sound with the gain cranked and the attitude knob all the way up.

For "maximum gain" I love EL-34's with ECC-83's and 82's as pre-amp tubes. In the "rock" channel with the gain and attitude turned up, using my LP Standard... it is the sound of rock!

As others have noted, it's a low powered amp, but because I mainly use it as a preamp that doesn't bother me a bit. In fact, I can't believe so many criticize this amp as not being loud enough for band settings. Aren't people mic'ing their amps and running them through a PA? Is their goal to have stage volume so loud it drowns out everything else... Yowww... I'm glad I'm not in a band with them!

To me, it's important to get the sound you want coming from your amp... then mic and send that sound out to the crowd. Controllable, great sounding tones. That's MY ideal.

I do agree that it's unlikely to use the tube swapping feature in a live gig situation unless you like running around with an oven mitt on or something! Those poweramp tubes get REAL HOT, and you've typically got to wait for 15 or 20 minutes to let them cool enough to pull them out with your bare hands.

It's SO easy to do this though, with the way the whole top of the amp just lifts off, that in a studio setting, it's perhaps the IDEAL real tube modeling amp. I can get so many different tones with my range of tubes... It's turned me into a real "tube hound".

Also the fact it's true class A, which provides that classic range of even harmonics, it has a VERY sweet sounding overdrive. And with the tubes I have, NONE of the "buzzing" type overdrive some have mentioned. I don't know what they're using for tubes, but it's not what I'm using!

I don't think I've ever been happier with any musical purchase. Perhaps my PRS McCarty comes close... But I don't use it all the time... I use THIS all the time. It IS my sound for all practical purposes now. I couldn't imagine NOT using it.

This thing is built like a "tank"... or, errr... like an AIRPLANE.

If any of you decide to take a peek at the guts of this, you'll be impressed with the "mil-spec" type hardware and componants used. Everything's nicely done, with no sloppy work I could see.

I expect everything to work great for a long time, and I'm confident the folks at THD would take care of me if they didn't. It's one of the advantages of a "small company" amp... they have to provide great service to be competitive.

Since I've never needed anything... I can't say.

But I've noticed some of the THD folks on the forums here. Nice.

I would expect any call to them to get a helpful result!

I've owned a number of other amps including various Marshalls, Fender's and other amps. I never really bought any type of "boutique" amp before, and I was a little nervous about it before I did.

I honestly didn't know much about tubes, the differences in their sounds and feel, or even how many different choices there were. But on the advice of a friend who highly recommened these, plus all the good reviews, I decided to take the leap on a used one.

I'm SO glad I did this.

I may eventually get another one so I can use them together for a "clean" and "overdrive" sound with an A/B switch live. But for now, one will do.

One other thing I didn't mention is how well many tube combinations respond to the volume control on my guitars. I simply make the sound of the "full-on" guitar as powerful as I want, then roll-off and let the sound "clean-up" nicely. My 6550 on the lower gain roll channel does this "perfectly" for a great blues tone, and it's fun having all the control from the guitar versus a stompbox or a gain channel where the gain increases all at once. MUCH more musical this way. Plus I can do it anywhere... even out in the audience or something!

I specially ordered one for Italian delivery. I received it in January 2003 so I'm guessing it was made in 2002. I didn't have a chance to try one before buying it, but relied on strong reviews. I play many different styles of music, but love the real smokey blues tone that makes you think of LesPaul/Marshall like Mick Ralphs from Bad Company, or Gary Moore in his blues phase. This is not a "change the patch every 20 seconds" amp. There is no channel switch and any major change like tubes, Rock/Roll, or HiV/LoV setting, requires a switch to stand-by.

There's plenty of power with the Univalve- if I needed anything louder I'd mic it and run it through the PA anyway along with the drums and bass amp. My problem is always quite the opposite- Can I get a could sound without blasting holes in the walls from volume? With the Univalve the answer is simply- Yes, I can.

Where do I use the Univalve? I use the Uni in the apartment running into the PodXT (using only reverb and cab sim from the Pod, and not it's amp sim). I use the Uni as a head in the studio. I use the Uni as a head and simultaneos pre-amp into my JTM45. I use the Uni as a pre-amp only into my JTM45.

The line-out/instrument-out is awesome on the Uni cause you can dial in just the right output. The Univalve has no fx-loop and no reverb, so you've got to find a way around that if you're not running it through a PA. Another great feature is the HotPlate which allows you to get good sounds with the built in db reduction.

I play a few different guitars: LP Custom, LP Standard, ES335, Peavey Wolfgang, Telecaster, and EC Strat. Each one has a distinct sound when played through the Univalve. Each pickup or combination of p/u is very distinctive, in fact, you can easily tell the difference between different brands of picks. The Univalve puts out what YOU put in. Touch is vital and I'd immagine that guitarists more talented than me must just love this amp. With just an adjustment of the guitar volume you can really clean up the sound- amazing. What you won't get is a compressed Pod-ish sound where most people and most guitars sound the same with the same patch. (I've got the PodXT and am not ragging on it- it's a different tool) The Univalve is all about tone. Anyone who can't get an AWESOME tone out of the Univalve doesn't know how to take the 20 seconds to change tubes.

For my Bad Company-ish sound I use a NOS6V6 powertube and a ATX7/AT7 combo and volume cranked up to around 8 this the LP just oozes tone and sustain. We're not talking about pedals or modeling, but 100% pure tube overdrive that is incredible. When I run this a/b using the speaker-out of the THD into a 4x10" and the instrument-out into the JTM45, I swear the tone would bring tears to the eyes of most guitarists.Ok, maybe my playing would be the cause of the tears :)

There are so many combinations between the
1. Power Tube (EL34, 6V6, 6L6, EL84, KT66, KT88, etc)
2. Pre-amp tubes (AT7, ATX7, AU7, etc etc)
3. HiV/LoV (amount of current to the power tube on the plate)
4. Rock/Roll channels (hi and low input)
5. Knob adjustments (with noticeable differences besides all-on or all-off)
6. Direct out to cab/Pre-amp/Both (you make the call!)

And this is all before guitar and speaker options.... can't really think of a more flexible product for awesome tones. Yeah, it's not as easy as turning the dial on the PodXT, but the effort is well worth it. I admit I spent another couple a hundred bucks on some great NOS tubes- but I'm looking for the best tone possible. I'm not looking for the best bang for the buck. The Univalve is one of the tools that allows me to achieve a NON-COMPROMISING tone that I am fully pleased with and would never have to make excuses for. You'll never hear me say, "It's not too bad considering it is only a ...." (fill in the blank). You'll hear me say, "Yeah, that's right- it's the little THD thingy there that is generating that tone!"

For Clean tones the Univalve can get many of those Fenderish or Voxish sounds, but I almost always use the Uni as a pre-amp. I just feel those clean tones need the reverb and the Uni lacks it.

Works for me.

The guys at THD are very helpful and have always responded to my emails with hours. There is also a forum where Ed is pretty quick to answer questions. The thing I like about THD is that THESE GUYS ARE GUITAR PLAYERS and not just salesmen. They are very helpful in helping you find the sound you are looking for.

I've been playing for about 20 years. For amps I've also got a JTM45 and Vox AC15. I also have a Digitech GNX-2 and a PodXT. I listed most of my guitars above. I love the Univalve and would buy another one if anything happened to this one.

To hear my review you would think I would reccommend the Univalve to everyone, but this is NOT the case. It is not cheap and it is not easy-to-use like a Pod. In order to get great sounds out of it, you have to experiment. I would reccommend the Univalve ONLY to those guitarists that are looking for the "Ultimate" tone and can afford it. For beginners or people that like someone to have already done all the tweaking for them, I'd suggest a CyberTwin or a Line6 or something of the such. While I LIKE the ease of the PodXT for practising with headphones (and the sounds are really pretty good), I LOVE being able to turn up the Univalve and take off for tone heaven.

This is a new Univalve purchased from Avatar Speakers (Dave is fantastic at customer service). I won't list the features, the THD website does that very well. I will say that of all the amps I have ever owned each control on this one makes a real difference in the sound. Moreover, there is an interaction between all the functions that allows for great control of the tone. It surprised me even though others in this column had mentioned the impact of the controls. I had to re-learn using controls. The single treble and base are actually more powerful than the T-M-B on my Marshall dsl 50 (which is a very nice amp). You can even use the noise reduction to cut some high end and warm up the sound. Bottom line is this amp is simple but has all the features you could want. The biggest feature is the ability to change the sonic character by changing tubes.

I use a Epi Les Paul with Seymour Duncan 59's and play lots of styles, but tend toward blues and rock. So far, I can get pretty much all the sounds I want out of this amp. I will agree with others, it is not a Marshall or a Fender. It is also not a one-trick pony, like some boutique amps. The THD has a clear replication of sound all its own. By changing tube mixtures and adjusting the very functional controls, you have a much larger pallet of sound to work with. I like the idea of changing the tubes to get a different coloration of tone. What any buyer needs to keep in mind is that you can "lock" into a particular combination of tubes and just run that. There is no mandate to change tubes all the time. I just like being able to get the different character without having to buy multiple amps.

At first I thought the amp was bright sounding, but it hit me that it is just very good at amplifying across all the frequencies and reproducing a very balanced tone. Most other amps do start with a circuit design that feeds a tone into the tubes but THD seems to have taken the approach of feeding a balanced signal into the amplification matrix and allowing the tubes to do the changing of the basic tone.

This is a quiet amp. I get a little buzz with some tubes -12AX7's seem to be noisier - but I put in JJs and EHs and they both are nicer than the stock ones. I have gone to a 12AU7 or 12AT7 in the input and you can't hear the amp. Even with the noisier tubes, when the noise reduction is on the noise goes away.

I like being able to go from a 6V6 sound to an EL34 to a KT66 with just changing tubes. I've actually had to screw the cover back on and force myself to play using a single power tube for a while. That is when I really started to understand how powerful the controls are.

I can dial in a clean that is very appealing to me and then go to the rock channel and get a smooth distortion. Keep it on the bridge PUP and turn the treble and bass on the amp down and you've got a scooped sound that is very aggresive. Put the treble to 10 o'clock and the bass to 2 o'clock+ and move the the neck PUP and roll back your guitar tone and you've gotten into that wonderful British sounding distortion. My favorite is the 6V6 in the roll channel with the amp volume up all the way and the 10 and 2 position on the T-B and you get that break up on double stops and power chords that is the essence of the blues on electric guitar.

When I have a tone that isn't quite what I have wanted, I have found that a little tweeking will get me there. Give me a few more months and I will be able to just dial in what I want within a few seconds. That may seem odd, but, like I said, everything on this amp has a purpose and an interaction with everything else. It is a real pleasure to use.

I know this sounds pretty simple, but the type of speaker used will dramatically change the sound of the amp. I am currently using a 2x12 that has a Greenback and a G12-30H. This sounds good to my ear.

I have put a KT66 in with 2-12AX7s on HiV and let it crank on the rock channel through 2 2x12 (equals a 4x12) cabinets and this amp can move some air. With powerful speakers like V30s you will be heard.

At the same time, you can run a 6V6 with 12AU7 in the input and a lower gain tube in the driver stage and you can play without the attenuator at a room level that really sounds nice, not like pale and week like low volumes on some amps. That is one of the great features - with the volume control down low this amp still has a beautiful sound.

From a distortion perspective, I like the ability to get the different types of distortion from the many power tubes. With the lower gain preamp tubes I can tailor the breakup to be warmer and sooner in the volume range. What I find really nice is how smooth the distortion is. I mean there is no oscillation in the tone - just a smooth crunch that is very musical and full of harmonics. You can hear th

This thing is built very well. I expect that it will last for a long time. It is lighter than most amps, but you can tell the level of workmanship is very high. I like that THD has made very few changes in the design since it was introduced. That means they can focus on quality of manufacture, not worry about how to fix design flaws (which they don't have). I looked at another boutique amp (at twice the price) and one factor in not going for it was that they seemed to be constantly tweeking the design and components. Each amp was a little different and that got me concerned.

I would gig with this without a backup (I only do small venues).

I have been looking at the Univalve forum and see that THD actively participates and listens. I do not expect problems, but so far the customer support seems very good. I had sent a couple of email questions before I bought mine and they resonded with complete answers and within 24 hours.

Been playing as a hobbyist for 10+ years. I've owned various Marshalls, Peaveys, Fenders and Boogies. Some time ago I decided tubes were the only way to go and the journey to get to an amp that matches the shifts in my sonic mood has been difficult. The approach THD has taken is just right for what I want. I love how responsive it is and how many characters it demonstrates. I find it plenty loud and, with the right speaker cabinet, it easily fills up my practice room and up to a medium venue.

I chose this amp because I was tired of a) not getting the sound I wanted from an amp or b) getting one or two great/good sounds but not being able to go beyond that. For me, this is a great amp and I do not expect to be changing it any time soon. It has a nice sweet spot and I can get to the tone I want without blowing out the room.

I can understand why there is no channel switching, but that might be a nice feature. It is not one that I am overly concerned about since I usually play out of one channel or the other.

Please see other reviews. Due to some unique features as Hi/Low voltage switch, adjustible line out etc... it probably deserves 10 (the harmony-central standards).

See the review below, I agree 100%. I obviously belong to those guys who like to try/change stuff. Spend some money on NOS tubes and good quality speaker cabs for the 10 sound.

Excellent build quality.

First class. I moved to Europe and asked some questions regarding the input voltage change. Since it's a small company you actually talk to guys who designed the thing. Very nice people to deal with.

The tube swapping is nothing new (cathode bias), but nobody before created something like the Univalve (with multiple fuses, hi/low switch etc.). Everything inside the amp is well thought of and the amp obviously took them some time to create it. The preamp is Marshall (not Andy), but it does have a sound of its own (SE configuration). If you are into brighter, Marshall-like sounds I highly recommend the amp.

Purchased in Dec 2001. Sincgle channel, built-in HotPlate attenuator, line out, 2 voltage settings, noise reduction. One thing that would be nice to have is a different kind of EQ system. I know that it's a type of EQ where by turning down the bass and treble, it effectively leave the mids emphasized (vauxhall type??) but treble control seems like it's NEVER effective in rolling off the high frequencies. Attitude control is interesting and it is not like a presence control at all. It almost feels like it's controling the amount of overdrive at the driver tube.

There are many who says that UniValve is loud enough to gig with. But everything is relative. Some ofthe tube configurations to get the volume isn't the best sounding however. More on this later. The thing is if you want it to sound "good", the amp will never be loud enough to gig with a band.

The feature of being able to swap tubes is addictive to say the least. You can can get various sounds but changing preamp and power amp tubes but the fundamental sound of UniValve (yes it does have a sound of its own) will always stays the same.

What makes UniValve interesting and addictive is also the weakness of the amp. Although the amp sounds mediocre at best (more like a fuzzy beehive), but it can achieve more than a couple of "10" sounds by carefully fine tuning tube configurations. Just be prepared to spend as much money as you did on the amp!! :-) Joking aside, just be prepared to spend some extra money in obtaining some lower gain preamp tubes. Low gain preamp tubes would bring down some of the brightness of the amp and it is a VERY bright amp in its stock configuration.

There are amps that sound sound the same regardless of what tubes you put in as long as you are using the tubes required by them. For UniValve, some of the current production tubes sound OK but it sounds MUCH better with old production tubes

While trying out various tubes are fun and educational, it can be quite frustrating, too. Especially if you were looking for some "plug-and-play" enjoyment. For that, you should look elsewhere. You will beed to dig deeper into the world of vaccuum tube and try out some not-so-common-guitar-amp-tubes from the 12A?7 family to fully appreciate what UniValve is capable of.

One thing to keep in mind is there are only a few power tubes that can withstand the Hi-V setting, old production tubes in particular. But if you "need" to get its maximum output of 15w, you have to tun it in Hi-V setting. But Hi-V setting is generally much more: trebly, bright, aggressive, fizzy, buzzy, extended treble range.... etc. So a lot of researches are needed to come up with the tube configuration that works.

In general, Lo-V setting sounds much better than Hi-V setting. But you won't get the volume, of course.

UniValve may also make you re-examine your current speaker/cabinet configuration.

For the rating: 5 out of the box but capable of 10

No problems so far. But then again, I am not the type to "throw" my gear in the truck after gigs, either. A case of some sort may be a good idea in order to protect it from wetness (rain, snow, etc) just because of the amps "cage over chasis" style.

I don't know since I have not had any problems with the amp.

This amp can easily go either way, Love or Hate. It is capable of some wonderful sounds but it greatly lacks the out-of-the-box experience. You may bring it home and plug it in then scratch your head as you say to yourself, "what am I missing?" If that is the case, do some research and find out what others are using that transforms the amp into a "10" amp. In summary, if you are a tinkering type, you'll love it. But if you are "plug and play" type, get something else.... like BiValve, perhaps.

Single channel Class A guitar amplifier. 15 watts. Controls: Volume, Treble, Bass, Attitude, Noise Reduction, Hot Plate, High Power/Low Power Option, etc. This amp can do any sound for any style of music. Those of you whoe are blabbing that this amp cannot do high gain, you are playing with the wrong equipment. I wish there was a channel switching option, but this amp is so cool...who really cares. This amp is LOUD, It won't hang with a 100 head, but when's the last time you even turned your 100 Marshall/Mesa/Soldano/etc. to 10? That's what I thought. The power on this amp is very useful, you can play quiet or loud all with great tone. I repeat... T O N E. No Line 6 crap will ever compare to real tube driven tone. Period.

I have 2 guitars that I use...an ESP GL-56 (George Lynch/Relic Custom) and a Carvin Custom 7 String (Koa body and neck, Quilted Maple Top, fixed bridge). I like to play music ranging from SRV, Eric Johnson, Joe Satriani, Dream Theater, Opeth, Arch Enemy...the list goes on. I am into both super clean sounding guitars (amps), and massively distorted; full out bone crushing; brutal death crunch. This amp can accomodate either style...assuming you have the right equipment. The head is relatively quiet...the louder it gets...the quiet hiss increases...but thats eliminated with the Noise Reduction feature (90%). I use various effects...tremolo, flanger, distortion/overdrive. This amp accepts all these really well. The rich tube sound is never in doubt...even with stomp boxes...the tone still comes through clear as a bell. Or a freight Train depending on how distorted you like it.

Recently purchased it, but it's built like a tank...so Iexpect it to shine on.

Fast responses to emails. When you don't have to service little 13-21 year olds it's easier to give better service. At least I assume most 13-21 year olds would shy away from this amp...because it isn't endorsed my members of Limp Bitchkik, or Korn, or Nickelback or some other crap.

I have been playing for 15 years and am basically self-taught. I run the Univalve through a Genz-Benz G-Flex 2x12 cabinet. If this amp were stolen I would file a claim with homeowners and get another one. I love how simple the Univalve is to use. I owned a Laney VH100R prior to this and that amp screamed. It was so so so loud it was too loud. I couldn't get it above 1 for practice volumes. If you had it on 3, your ears would ring all night long. I was looking to get a new amp and was shopping between the Univalve, a Mesa Boogie DC-10 Combo and a Naylor prototype. The Mesa was sweet, both distortion and clean sounded great...but it was sold before I went back to the store. The Naylor was $2500 for head and cab. Sounded amazing but c'mon...is there THAT big of a difference in tone? Maybe there is...so some day I might get a Naylor. The Univalve drips tone from every tube (3) on it's chassis. I love the fact that you can swap out tubes to achieve different sounds. Real Modeling Amp...Tubes that sound like music from the 60's, 70's...even 90's.

As described by other below. The main point of this amp is THE tube sound, not effects or gimmicks. In that contaxt it has to be judged hence - 9.

The sound is DIVINE i.e. as good as it gets from any sellection of tubes and with decent guitar playing :-)

There are only 2 questions that require an answer:

i) Is it sufficiently laud for a jazz concert when you need CLEAN tones rather than a sweet, warm distortion.

Here I am not 100% sure, but the clean sound is 3 dimensional.
Some people may need the BiValve - if they need clean header.

ii) Is it sufficiently portable so that you can easily use it in any gig?

Here the answer is YES.

Like a tank.

Very helpfull.

I play since 1960 and do I wish we had amps like that back in the '60s and even the '70s ... this is one of the very best sounding amps I ever played and I tested them all: Vox, Phillips, Selmers or Fenders and Carvins in the '60s, then Marshalls, Hiwatts, Orange and Mesas, Laneys, H&K, Reverend, Cornford, Kendrick ... all the way to Songworks, Koch, Engl or Ashdown Peacemaker

I like the sounds of this amp BUT I still didn't buy one actually: I am very hesitant as I am not sure whether for my jazz band stage gigs I need the BiValve or the UniValve: the former has more clean headroom yet this one is cheaper and in a way has even sweeter distortion. In the meantime I am using the THD hotplate with an Ashdown Peacemaker 40 combo - until some of you guys writes to me and assures me that this amp is THE amp for the clean jazz and my gigs ... otherwise I may buy the (VERY heavy) BiValve ... so, please write to me directly - THANKS.

Features have been listed in previous reviews. It's a debate on whether there are enough or not. For me, it's more than plenty. Of course I come from the old school where I think the best system is comprised of dedicated components each with a single specialized purpose. Yeah it's more expensive and complicated but the end result is what most people spend their entire lives and a lot more dough trying to achieve with single units that are feature-laden.

First of all, the statements that this amp is not loud enough for gig's are utter bullshit! Even if for some novice reason you are not running a full mix through a FOH system this little baby can rip your head off! Sounds to me like to many kids are cranking hundred watt amps in their bedrooms and going deaf rather than learning how to actually play a guitar and learn about tone.

Okay! Now that I'm done venting.

I picked up this little monster on ebay with a couple of replacement tubes and a yellowjacket. Being a gear-junkie for the last decade or so, I now own or have owned numerous brands and combinations of amps, guitars, effects, etc.

After years of searching for that magic piece of gear the revelation came that the magic of tone starts with me. Unfortunately numerous other's have fallen into the same trap as I thanks to great marketing from the manufacturers and the endorsements of our heroes. So I say to you, save your hard earned money and instead of getting that next stompbox that's sure to make you sound better, try saving your money or use it to purchase some lessons. Remember, no matter what level of musicianship you achieve, there's always more to learn and someone out there to learn it from. Even so, I still have an equipment fetish and mainly buy gear now because I'm not really into anything else as far as spending money goes. Hence the Univalve.

This little beauty is definitely a diamond in the rough as far as tone goes. As per other reviews, the sound generated is dependent on numerous factors: tubes, speakers, instruments, etc, and especially your ability and technique as a player. In a nutshell, regardless of the nuances of different tubes & speakers, this little guy produces a very basic yet very pure electrified guitar tone. You've got two choices, low gain or high gain. The neatest thing about both is that it is harmonic gain generated from power tube saturation and volume as well as pick dynamics and technique. If you want to enhance the sound or effect the tone, that's where all the features come in. i.e. line out, attenuator, voltage select, etc. The imortant thing is that the building blocks of a good sound begins with a good base tone from guitar and amplifier. From there you can add the effect's, E.Q. or increased power. That's what this amp offers and that's why the folks at THD have engineered this amp with the features it has.

In short, if you are looking for something you can plug into and sound like your favorite dude on record, do not buy this amp. Unless your dude is an old blues, country, or classic-classic rock player. For bedroom wankers & wannabee's try one of the feature laden modeling amps. Their inexpensive, and are full of everything but good tone.

Top notch! If it goes down, chances are it's just a tube! And it ain't hard to figure out which one.

Have yet to need it.

I am a professional musician that has been playing for so long I can't even remember how long. I use all kinds of gear & guitars depending on what the job requires. I tend to vent a little in my reviews due to the fact that I am disgusted whith the Drop-Tuned Buzzsaw nation of so called players that sound like shit, play like shit, and are shit. In other words, I'm getting old.

As reviewed by everyone else. Suits me.

I have to defend "anonymous" here. I so wanted to like this amp - even had a space cleared for it at home; BUT - it just didn't work for me. I swapped tubes, cabs, guitars, high volume, low volume - you name it - and it just didn't have the magic to my ears. I nearly bought it anyway - I wanted it so much. A friend of mine once said that if you consider an amp to be analagous to a piece of wood, you can change the colour by changing the volume, tone controls, valves etc, but you can't change the grain. In this case the grain didn't seem to that special to me. I still want the amp though and might just try another one "just in case".

Looks to be beautifully made, part of the reason why I still want one.

N/A

Aaaargh, I might still buy one to use as a paperweight.

No channel switching is the main drawback. I overcome this with a super duper 2 in 1 as a boost in the low gain channel, which overdrives the tubes very nicely as if it were in the high gain channel. This "fix" cost me $250 though.

Other than that, the features are simple and perfect for my taste: I've never been a big fan of effects and I find a reverb "effect" to be artificial in any amp. I generally found myself using reverb to overcome a bad room (or outdoor venue) or to overcome an amp that sounded thin and stale on its own. This amp sounds really good on its own if you have a good room to play in--room can make quite a difference. The two music stores I sampled it in sounded drastically different--one was blue note music in Berkeley, CA , which has a high ceiling and lots of room to breathe (sounded great) and one was Gelb music in redwood city, CA, which is a tiny, sliding glass door "soundproof" type miniature jam room that sounded just awful. Sounded like different amps.

1991 Gibson Les Paul with factory pickups ---> zvex super duper---->univalve

I use a Genalex KT88 and it sounds like angels singing. Get ready to spend money on NOS tubes, because once you start trying some and notice the incredible difference in sound and variety of sounds that can be acheived with different tube settings you will be amazed. Lots of people are happy to spend $100 or more on some plastic stomp box--spend less than half of that on a Tung-Sol 5881 and a decent 12AU7 for the driver and get a dreamy sound that is much like buying a new *amp* and furthermore real--not some digital gimmick.

I play rock music, ranging from pop-punk to heavy riff rock to texas blues

I can't rate it highly enough I never give 10's so a 9 is high for me.

I admit that I have not played a gig in years and probably never will again. If I do, this amp will by mic'd or I will use it as a pre-amp into something with some heat. It is louder than necessary for the jams with buddies and I've never had the slightest problem in the last year.

They go above and beyond the call. I am an incredibly picky person (even for an attorney) and I called the day I bought it because of a perceived problem with it. There actually was no problem, but suffice it to say that they offered to make me whole for even an imaginary defect if I wanted to send it straight to them. Very kind and helpful over the phone and email. A second time I interacted about a goofy tube from a WWII walkie talkie and they even answered my tech questions promptly and thoroughly.

I've been playing almost 20 years. I have owned various Fender and Marshall amps (and I'll admit to having owned a crate and a peavey, too, much to my dismay--those were low points in my life, gimme a break). I only play my Gibson Les Paul now. I own some Fender strats but haven't played them for years. I don't even know what this amp sounds like with them.

First, if you need a high power gigging amp--go no further, you shouldn't but this amp for that. That being said, I don't want this to irritate anyone by saying this, but here are my thoughts: Every guitar player thinks he has good taste. Every guitar player thinks he has a good ear for tone. Not all guitar players have these qualities--even if they can play the guitar well. That is just a simple fact.

This amp is for the afficionado with a good ear and appreciation for tone. It is for a mature ear. It is not the end-all, be-all of guitar amps. It does not do everything. But it has phenomenal clean tones and glorious edge-of-breakup distortion tones and heavenly harmonics when the distorion is turned up high. I'm serious. If you get some time to try one in a good room, with a Gibson Les Paul, playing through a THD cab, give it a go. Ask the guy at the counter if you can swap in a KT66 and try that, too. Give it another go. Don't give it too much gain and demo it with the hot plate off entirely. (Yes, there are issues with attenuators of all types, don't penalize the amp because they gave you a free feature--would you like it better if you had to buy your own attenuator separately? Give it a rest.) Ok, now if after playing it under those circumstances you don't like it, I recommend trying it in a better room. If you still don't like it, (and I don't mean this as a dig,) I'd say you probably should wait a few years until your ear has matured. If you're a teenager or a beginner, get one of those line6 amps and a metronome and spend a decade just learning how to play your guitar. Then go play one of these and you will have your epiphany. I will now shut up and play my guitar.

My Univalve was made in 2002 and I have had it for about 7 months. I won't reiterate the controls, etc. since everyone pretty much has covered that. There are things that many people feel make this amp not so flexible, such as the lack of an effects loop and channel switching, but those things are not really what this amp is about. Others will disagree, but sorry, this amp is not powerful enough for a rock gig on its own, even through a 4x12 cab. That said, the built in line-out works beautifully to drive external power amps, and you could easily put together a rig that would suffice for gigs. The other option would be micing the cab. Factor in the built-in attenuator, dummy load, and ability to drive virtually any impedence cab and I think this amp has some really nice features. The tube swapping feature is pretty cool, but basically you'll play with this feature for awhile and settle on a particular set of tubes that you like and stick with them unless you are tinkering in the studio.

I WOULD give the sound a 8 or 9 but let me qualify that by saying that to achieve a '9' you better be willing to spend some cash and experiment a lot to find the tone you are after. Frankly speaking, there are combinations of tubes/speakers/guitars that sound absolutely horrible with this amp. That said, there are other combinations that flirt with an outright 10 in the sound department. I think most people with this amp would agree that how it sounds is, more so than some other amps perhaps, dependent on your particular playing nuances and the tube/speakers/cabinet type. I would agree with other people that the amp tends to be light on bass response and can be a bit trebly at times. Again, different tubes/guitars and speakers all influence this greatly. I think that the amp tends to sound best with hotter humbucking pickups (eg. my Les Paul), but there are good tones to be had with weaker strat-type pickups (both humbucking and single coil). With my strats, I tend to favor a boost of some sort to kick the amp a bit. The distortion can sound fizzy, particularly if you use the hotplate. By far, the best tones come when you are running with the hotplate disengaged. If I had to characterize the distortion I would say that with a strat you are firmly in Jimmy Page land. You can cop early tones as well as Physical Graffiti-type tones fairly easily. With some vintage PAFs, you can get in the ball park of early VH. I don't see how anyone could say that this amp would do metal unless you put some sort of distortion/overdrive pedal in front of it. This is not to say that this amp is an exact mimic of those tones -- far from it. These are just good tonal references that many people are familiar with. This amp has its own distinct sound, and part of that (I think) stems from the class A nature of the amp. The attack is very immediate, and this reveals everything in your playing both good and bad. It does have a different feel from a Marshall head, for instance. Bottom line, in my opinion, is that if you want a Vox or a plexi you would be better off buying one. If you are willing to invest some more cash and lots of time to find some interesting tonal flavors that are around these types of tones then this amp might be for you. I would say try before you buy, but it is unfortunate that the tubes that ship with the amp are just about the worst combination I have heard. I probably wouldn't have bought the amp if I had just plugged my strat into it and played it in the store. I bought mine by mail-order, at a time when they were extremely hard to find. Initially underwhelmed by the amp, I have now found a set-up that really sounds pretty good to me.

Seems to be a very heavy-duty piece of equipment. To early to tell, and I don't gig anymore so I can't vouch for road-worthiness.

Hard to say until you have a real problem, but the folks at THD (Ed in particular) are easy to get in touch with and seem committed to customer satisfaction. I wouldn't anticipate problems in this area.

I've been playing over 20 years, several years profesionally and quite a few semi-pro. I bought this amp to have a somewhat lower power alternative to my rack rig for practice, basement jams and for use in the ocassional recording that I do. The hype around this amp really contributed to my purchase decision - I mean who could read that Guitar Player review and not think that this amp is IT? I am only giving the amp a 7 overall because I want to be realistic. I really believe that you have to spend a lot of time with this amp and be willing to invest at least as much as you spent on the amp itself in tubes, and even more $$ if you need a new cab or speakers. I think if you bought this amp with your last pennies and needed it for an every day cover band you would be probably be disappointed. The amp is more for the tinkerer or the studio musician. What you get is an amp that is extremely well-built and has the ability to sound absolutely heavenly if you spend the time to work with it. If this time/money investment is not for you, or you are just looking for a good plexi sound, then I would say go buy a Marshall. You'll be happier in the long run. I am definitely keeping the amp, as I have grown to love it. I don't say this because I have money to burn and a stable of amplifiers - I don't have either (although that would be nice). For me, the amp is really great, but I can easily see how for others it would be a minor disappointment. Your best bet would be to find someone who owns one and has a decent collection of nice tubes and spend a few hours with the amp before you make the decision to buy. Aside from that, you'll just have to take the plunge. There are many, many GREAT tones in this amp, but whether or not they are the tones that are going to stoke you is hard to say.

You already know them all. The ability to swap tubes is cool, but how often do you do it? Not especially usefull in my opinion. The HotPlate is nice, but the sound gets pretty thin if you attenuate too much. Not a complaint, just something to be aware of. Lack of channel switching and the inability to switch between channels without unplugging the guitar is a huge drawback for live performance. The Line Out is nice and sounds good with a RedBox.

Used with a Les Paul Custom, an ES-335, MIA Strat and Telecaster, with Celestion G12T-75 loaded Marshall cabinets.

I really, really wanted to like this amp, but just couldn't. It is capable of producing good sounds, but there's no easy way to switch between them. The roll channel produces great clean, especially with the Strat, but really isn't loud enough to be useful. The Rock channel produces as much gain as you could possibly want, but is very fizzy, not smooth at all. Compared to a Marshall, there's a serious lack of bass also.

I like to set my amp and forget it when pefroming, just controlling everything through the guitar's volume knob. I couldn't find a way to do that with this amp. Setting up to get a good distortion sound, the amp wouldn't clean up at all. A good clean sound isn't available at a loud enough volume.

For recording, this is probably a pretty good choice, For performance, I found it useless.

Other than a loose fitting power cord, I never had any trouble in about 3 months I had it.

Excellent. Ed is easy to get a hold of, and obviously takes great pride in his work and company's products.

I've been playing 30 years. I tried the Univalve because of all they hype. Tried a variety of tubes and just couldn't get it to work for me. I sold it, and wouldn't replace it if it were stolen or lost.

To those who say the Univalve cannot nail the plexi sound, here's a suggestion: Put a 12AU7 in the driver position. This will really focus the distortion. IMO, the stock tube setup is great on the roll channel, but to much for the rock channel. Also, for the "brown" sound, try a Valve Arts KT66, a 12AX7 in the pre, a 12AU7 in the driver, and keep it on low voltage. Add a strat with a bridge position humbucker, and you can be EVH (talent permitting).

2002 THD Univalve 15 watt head. Most of the specs have already been detailed. I use the amp for hard rock and punk rock. This amp is really easy to use and pretty much fool proof. No channel switching, just volume, bass, treble, and basically a presence knob control the tone. The selection of tubes and the power setting also help to adjust the tone.
The features that really stand out to me are
1. easy swap out of power tubes for different tone.
2. only a few knobs on the amp to mess with. (more time spent on playing than turning knobs)
3. built in power attenuator (get saturated tube tone a low volumes)
4. power selector (high or low voltage)
5. adjustable direct out -> here is the cool part, unlike most heads like marshalls, you don't have to connect a speaker cabinet or dummy load to the univalve. it has a built in dummy load that is activated when the speaker jack is unplugged. This is a great feature for recording direct. You get a cranked tube sound without having to wake the neighbors. I only wish there was a built in cabinet simulator too.
6. Size, this thing is small and light in comparison to other full size heads. You can carry this amp in one hand.
I'm giving this an 8 for features because it has most of the features I look for in a head. I don't use effects loops and don't really do channel switching but since this amp doesn't have those features I will give it an 8.
where this amp really shines in versatility is the abitily to use a wide variety of power tubes. you can get a lot of different tones from this unit, but it isn't as easy as turning a knob. you've got to change tubes (easy on this unit- no re-biasing needed) and try different speaker setups.
oh yeah, the head has a little yellow light on the front used as a noise suppressor. I don't use it because it takes away some of the tone I find desirable.

I use this amp with gibson les pauls and run it through a mesa 4x12 recto cab. Even though this is a 15 watt head, it definitely cuts through the mix when used with a 4x12. Pop in a 6550 tube and you can get plenty loud. The feedback isn't as sweet and easy to control as on some of my marshalls. The playing tone is great, especially for open chords. You can really tell a difference in tone when switching out the tubes. The EL 34 crunchs best for tight stacato type riffs and muting, the 6L6 is good for non-muted chording and soloing, and the 6550 gets a huge, open sound good for open chords and riffs that are not muted.
I don't really play to much clean stuff but the amp seems to have good clean tones too.
I was concerned that this amp wouldn't have enough distortion for my style of music or it wouldn't be loud enough to cut through the mix.
No need to be concerned. Plenty of distortion and power.
I used this head exclusively the last time I went in the studio. I did one track with an EL34 and another track with a 6L6. Then I blended the two tracks together for a very full guitar tone.
In the past I have always used marshall heads to record. I can't say that the THD sounded better than a marshall, but very close. I was able to distiguish individual notes better with the THD and I think it has a better signal to noise ratio. The marshall gets way better feedback though. This may be because the THD is class A. I don't know.
I'm giving an 8 for sound.

This amp has been reliable so far. Played 1 gig with it and 1 recording with it. I like my marshalls better live for the feel, and feedback. I don't bring backup amps (who does) to gigs, only backup guitars. I mainly use this amp in my bedroom directly to a boss recorder.

Customer support has to be a 10.
I've had every email answered within 2 hours of emailing THD. They are very polite and thorough in their support. I emailed at least 3 times before buying and 4 times since buying.
I have never experienced customer support like this from any company.

If you like channel switching or effects, this amp probably isn't for you. If you usually play guitar-cable-amp and need a light/portable amp that sounds good, and can get a lot of different tones this is for you.
Since you only need 1 power tube, maintenance is cheaper and you don't have to take it to a repair shop for biasing.
The built in dummy load should not be overlooked. If you power up a marshall without a speaker cabinet attached to it, get ready to blow your OT and get out your wallet. Marshall should add this feature for convenience and safety.

I bought the amp july 2001 #185 guess it was built in june 2001.(ED?)
Features are as simple as they should be.
You won't be sitting around playing with buttons, you will actually have time to play your guitar.
I have spent a lot of time switching tubes but I seem to keep going back between three combos.
If you can sit with this amp cranked(except 6V6,El34?) and not have your ears ringing for an hour then you are *already* deaf.
I can't hear my 500 watt stereo(heard clearly from a half block away) over this 15 watt amp, and that is with a 6L6 on Roll(Low Input) cranked.
Room placement seems to make a huge difference with this amp although it may be the cabinet(THD 2x12) I am using.(?)
I don't really use the line out much. Although I have recorded with it direct onto a MD recorder with impressive results.
Instrument level out is also colored with the amp's tone(same as line out).
A/B switching would not work with this amp due to the amount of gain difference between the two.(Circuit won't allow both jacks to be used simultaniously and there is no way to change it, short of a new board design.)*Fulltone FAT boost works very well with this amp*(Simular to the THD internal high gain circuit)
I rarely use the Hot Plate I like to feel what I am playing. It seems to work alright but I just like loud music.(WHAT ABOUT THE NEIGHBORS?)
Noise reduction equals tone reduction and a slight delay but its alright on slower stuff.(Cuts mostly into highs but also a little bottom end.) It isn't really necessary there is no excessive noise with this amp but it does offer yet another tonal color.
I am totally satisfied with this amp because I don't like to have to spend all day playing with buttons etcc.. it may not be for everyone but I love the simple concept!
I am giving it a ten on personal preferance.
**I wish all my equipment was this SIMPLE AND VERSATILE!**

*I am using all strat style guitars with single coils, Fend SRV's , Suhr V60's , Fend TexMex.I am very happy with the sound from the singlecoils. I haven't had a problem with noise as I noticed in some other reviews. Maybe they need to shield their guitars?

*This is a very versatile amp for a vintage style tube amp I can easily rough about any tone out of a 6L6 and tweak it with other tubes to a very close tone of about anything tube based.

*This amp has its own playing characteristics you can really hear every note or mistake you play and the sound comes/cuts through directly. (Other amps seem like they have a delay after playing the THD.)

*As far as distortion levels It covers the complete spectrum availiable from the power tube used. This amp is very good at what it is capable of, and that is driving a tube sound from clean to infinity.

*Clean as clean, high low whatever, "Just put that attitude down buddy".Just wish everything I buy were as clean.

*Although I wouldn't go so far as to suggest it for a strictly metal crunch type distortion amp, it can get there.(If you need an explanation as to why then you probably don't need this amp.)

Favorite set ups:(Knob contols estimated!)

6L6 Svetlana: Power + 12AX7 Jan: Input + 5751 Jan: Driver + Roll: Input + Full: Volume + Full: Treble + 3/4: Bass + 3/4 Attitude + On: Noise Reduction + Off: Hot Plate + High: Voltage = SRV's later smoother stuff (Variation: Low Voltage + Noise Reduction Off)

6L6 Jan(Stubbie): Power + 12AX7 Ei(Low Noise): Input + 12AX7 Jan: Driver + Roll: Input + Full: Volume + Full: Treble + 3/4: Bass + 3/4 Attitude + Off: Noise Reduction + Off: Hot Plate + High: Voltage = Strong bottom end and SRV's cutting full sustained bends like in Texas Flood

KT 66: Power + 12AX7 Ei(Low Noise): Input + 12AX7 Jan: Driver + Roll: Input + Full: Volume + Full: Treble + 3/4: Bass + 5/8 Attitude + Off: Noise Reduction + Off: Hot Plate + High : Voltage = A Dr. Z's milkshake

I have had no problems with the amp itself.
Although I did blow a 7027 tube in it(on high voltage), which took out both of my preamp tubes which were the new svetlana AX7's.(victim or crime?)
This 7027 tube is not listed on the amp chassis but was in the preliminary write up by THD as a useable tube.
I didn't loose the fuse and there was no damage to the amp.

I got my 2x12 THD cab slightly used and found there was a cool solder in it after it finally let go after almost a year's use.
I quickly shut off amp and didn't suffer any damage to amp or tube loss.(again no blown fuse)

I would trust this amp it is very well built inside and out and it has some cool stuff written on the circuit boards and some not so cool stuff.(If you can read this you have void your warranty)I must have used a mirror:)

Warranty ?
Customer service is great quick response even to stupid questions.

I would like to see the final Owners Manual Released with input output ratings balanced or unbalanced and possibly a schematic.
Maybe even a tube for tone chart.

I Love this amp!
.

I just wanted to make one thing clear to people reading these reviews in consideration of buying this amp. Ive seen lots of ignorant reviews on every product out there were people just dont get it, dont understand, or are just plain stupid. If you dont like the tone, thats respectable, but you know half of these bad reviews are due to ignorance.

No matter what hype THD or reviewers put out there this product was not designed to be a bedroom jammer. The whole idea of great sounding power tube distortion at speaking levels is an issue in the amp design world. The fact is 15 watts, 10 watts, shit even 5 watts of class A is very loud. THD knows this. Budda knows this. Every boutique amp manufacturer knows this. Some very small companies do put out amps that are bedroom/speaking levels. Even 1 watt is too loud for an apartment. Some of these amps that are being prototyped are 1/2 a watt and less. The problem is partly becouse despite what people say, theres no huge market and sending a low signal to a high rated speaker will always sound bad among other things.

I just want to settle this issue for sure for people who may be wondering and seeing mixed reviews. 7 watts is said to be louder then a trumpet. Most people consider the sound of attenuation bad past a few Db cut (not everybody but most.)Ive seen bad reviews on every amp out there and I know its becouse alota kiddies (who lie and say theyve been playin 10+ or whatever) buy an amp from reading reviews and play the amp in thier bedroom. It just doesnt work like that. Ive seen some of these people evaluate 100 Watt Marshalls and I emailed them offering suggestions to use when giging and it turns out they turn the amps volume to 1 in there bedroom. Then I say why do you own a 100watt or really any Marshall period.

Number 1. Make sure this amp is really what you need.
Number 2. If you dont gig but want to have an amp with great tone in case you do. accept the fact that your probably not gonna like your tone at home at low levels.
Number 3. Realize that cabinet construction, speaker make, guitars, pickups, cables, pedals, tubes and the room you play in all make a notaceable difference. Some more than others but just the same. Ive seen this alot were people are using shitty pedals and cheap cables and wonder why thier gettin so much buzz.
Number 4. Realize if you buy a product everyone is raving about and you think it sounds like the worst garbage and is completely unmusical you may have gotten a faulty product. There is no company out there that produces 100% perfectly working products. Especially after traveling through shipping. With so many parts, its likely that one part may be faulty or not to spec and it will mess with the overall sound.
Number 5. Make sure the tone of the amp is really what you like. Youd spare alota grief if you didnt try out a Vox AC30 to get Dimebag Darrels tone and then posted a bad review and didnt say why or were specific. Ive seen that type of thing alot too.

The following is a great site not only for amp info but for the problem, products and solutions to getting cranked sound at bedroom levels. The only sure-fire way Ive found to do this is to build speaker isolation boxes.

http://www.amptone.com/

Please realize Im not attacking any ones review or stating this product is good or bad (although I do love the UniValve) i just want to remind people not to forget that just like every other group of people, these review bases sport alot of morons.

Every pot, switch, and jack is well thought out. I love this thing as a main amp for rock, or as a slave in my bigger rig (it sounds great in the normal channel of a Fender and allows for multiple sounds).

There are some nasty comments below (both pro and con), which have led me to submit this second review. Of course, this amp may not be for everyone, but I think the majority of those who slam it don't understand it. A/B'd against an old plexi, I'm sure the plexi will be better, especially considering the power difference. And a blackface Fender Twin will have a better clean tone. However, vintage examples of these amps go for two or three times the price. Modeling? Still not there for me. Vox modeling amp? Lots of tones, a cool, very flexible output trick...but this and other modelers don't FEEL right to me...it's subjective. Sure, you can get a million convincing sounds with a button push--and that's fantastic--but they lack certain nuances that are important to me...TO ME modeling amps are still a little sterile, and for a serious gear head, it saps all the fun out if the "exploration" is done for you. I can get all of the basic vintage amp tones with the Univalve, but the difference is that I can tweak it to feel right as well. So, if you need 10 amps at the push of a button, buy a modeling amp. If you want an authentic plexi or blackface or whatever, get a loan and get one. HOWEVER, even if you have those, this amp is a lot of fun, and yes, it has it's own sound and vibe. Are there others? Sure! Is it driving them nuts that this amp is doing well? Who cares! Apparently, THD did something right that they didn't...

I mainly use this with humbuckers, but it sounds great with singles as well.

The main complaint seems to be the aforementioned "buzziness." Yes, it is correct to assume that speaker cabs can rectify part of the problem. Everyone has to find his own favorite...for me, Weber Chicago and ceramic, "N" cone speakers do the trick. For others V30s in a closed back, or a greenback 4x12, or alnicos...whatever, it's subjective. Based on info from THD, I nuked the buzziness by changing the driver tube to a lower gain factor (instead of 12AX7, I'm using 12AU7, but there are others inbetween: 5751, 12AT7, 12AY7, etc.). If I leave a 12AX7 in the input, I still have lots of gain...

Trying one brand/model of tube is also selling yourself short. While there seems to be only one 6550 that's widely accepted, there are at least 2 or 3 EL34s, several 6L6/5881s, 6V6/6K6/6F6s....etc etc...if you're not into all of that, don't buy the amp. I think the stock tubes are probably the worst combination I've heard in it (though not horrible)...and I guess THD does that because they want to minimize tube failures...this, I think is a shame. Nevertheless, there are much better choices.

The line out sounds great as well. While it needs a cab emulator or something to go direct to a console, it is fantastic into the front end of a clean amp. I've not tried it with power amps, but understand that this works well also.

I've had mine for 7 months. No failures or hints thereof. On gigs I carry a Fender Twin or Vibrolux, Univalve and a pedalboard. I slave the Univalve into the normal channel as another overdrive choice, but it is also available as a backup amp if the Fender dies.

I've gotten fast accurate answers to questions...in fact there's a forum (www.univalve.net) where Andy and Ed from THD, along with many users exchange info.

Over the past 30 years, I've had many amps, including 7 Marshalls, 6 Fenders, 1 Mesa, rack rigs, etc. This is certainly one of the coolest. I loved my 60s small box Marshall, my JTM45, and others, but they would be WAY too loud for what I do now.

As mentioned above, I could get lots of sounds from one of the modeling amps on the market, but I don't need that, and, to me, they just don't feel right.

It would be nice if this amp had a way to tap both "channels." Of course, you can use the guitar's volume to clean it up, but I have trouble moving from super clean to sailing overdrive using the volume pot...

The only other small issue I have is that KT66 tubes don't fit under the cover. They sound great, but I won't gig with them because of this.

Nevertheless, I love this amp!

Brand new. Super versatile recording amp. Everyone knows the features, so I'll skip that. More than enough power to drive a variety of enclosures. Used for studio recording. Waiting on the 30 watt version to use live.

ESP/LTD H-100 w/Dimarzio Tone Zone bridge pickup. Gibson Les Paul Custom w/Duncan Invader bridge pickup. Fender Jaguar (stock). Charvel Model 1 w/Tone Zone. I play indie rock/soul. Guitar driven with female vocals. Fits my style great. Very alive and uncompressed sound. I use a variety of NOS and JJ tubes with great results. I would highly suggest playing with different types of preamp tubes as well. For someone with the time to experiment you can get some killer tones from this amp.

Just got it, but it looks well made.

From what I hear the guys at THD are top notch, but I haven't dealt with them so I have no opinion.

For recording artists this amp could save a lot of back ache and car space. Just pack a load of good tubes, a few guitars, and the THD Univalve and your set. Just make sure the studio has a few good cabinets or some good preamps to go direct. All and all I feel this is a break through product that any good studio musician or recording artist should own.

Two channel, non-switchable, all tube class A amplifier. No effects loop. Line out. 15 watts RMS (lower for some tubes).

I have to wonder why some people bash this item, it is a real gem in my opinion. I am mostly trying to get a ballsy distorted rock sound, and in the Rock channel it is easy to nail the tones that I want. If you want AC/DC, use the Roll channel and max the volume. It's puzzling how some people say they can't get a good tone using the Univalve, makes me wonder if they a) don't know what good tone is, or b) have some ulterior motive to bash the product. When I see people post "comprehensive" reviews after 2 hours of use with stock tubes, I have to shake my head a little. I've had this amp for 3 weeks, swapped some power tubes, played it several hours per day, and I have barely begun to scratch the surface of what it can do. A few rules of thumb:

1. Use humbuckers. I don't care much for the way my Strats sound with this amp. Of my guitars, I like the way the Les Paul Classic sounds with this amp the best (stock pickups). Second would be my Music Man Axis, followed by my LP Standard and Seymour Duncan Custom in a Kramer. The only single coil pickups I really like with this amp are on my '52 Telecaster RI, has a kind of dark piercing snarling tone that is cool.

2. Avoid active pickups. I have a Strat with single coil EMGs. Sounds really flat no matter what I do. I also have a dual humbucker Carvin with active electronics - also sounds flat and lifeless. Supposedly the amp was voiced partly with a Steinberger using active pickups, so I don't know why I can't get a good tone with mine. Some have reported good tones with EMG 81s so maybe it's just me.

3. No reverb on amp - play in a big hall if possible. When I tried it in the store, it sounded OK even in a cramped little hallway with carpeting. At home, I play in a large room with hardwood floors and 20' ceilings, and this really allows the sound to breathe. Some of the complexity of the tone is lost if you are playing in a small or dampened space.

4. Noise reduction and Hotplate: leave these off and use full power if you want maximum tonefulness. Each of these colors the tone in a different way. Noise reduction does reduce noise, but the amp is already very quiet so it's not much of an issue. Noise reduction reduces the upper frequencies so it is like a reduced high end eq. The rest of the tone is pretty much unchanged. The Hotplate changes the overall tone, even when turned to max volume. It tends to compress the tone and causes more distortion at same volume levels. Both are useful but again, for full on tone keep them both off.

5. Use a good cab. Some report good results with open back cabs, I use stock Marshall 1960 4x12s and they sound great. It is LOUD. 15 watts is more than enough for a small venue.

6. Use line out for wet/dry operation - one complaint is that there is no effects loop. The THD guys say that this would defeat the tonefulness of the amp - the Bivalve is supposed to have one. I use line out to a multiprocessor then to a solid state amp to add some delay.

6. Hi-Voltage vs. Lo-Voltage: some people report burning out tubes easily on the Hi-V setting. I tend to prefer the Lo-V setting, it has more definition. Hi-V with 6L6 tubes gets a heavy Rectifier-type vibe going. I don't like Hi-V with the EL34s.

Have only tried a few varieties of EL34s and 6L6s so far. Next I'll play with preamp tubes and more exotic power tubes (like the KT88)... I like the stock tubes fine, some people don't. But that's part of the beauty of the amp, just swap it out for whatever you like best. I have to give this category a 10, and it is not given lightly.

Has been solid, well constructed. I have heard early models had a tendency to fry tubes on the High voltage setting. The setting was subsequently modified to reduce this problem. Some have complained of a high frequency buzz, I have not experienced this.

www.univalve.net and www.thd.com are good sources of information, overall they seem very helpful and eager to respond to customers

If you want a modeling amp, buy a modeling amp. This amp is NOT for those who want 200 patches with various effects. It is for those who want maximum tube tone, with few frills. The tube swapping is a nice feature but DON'T even for a moment think that it is some sort of "tube POD". It is not. The Univalve is a distinctive tube amplifier with its own sound. It can come close to some of the classic amp tones out there, but don't buy it thinking it will nail those tones. I tend to like the UV better than the classics anyway, but that is personal preference. And if you buy an amp without testing it in person, you are the only one to blame if you don't like it. Too bad. And if you test an amp briefly and dislike it, why burden us with that limited experience? Case in point, I tested a 5150 II and I thought it was horrible. But I don't post a review of it - because I didn't have the proper experience. I'm sure with the proper tweaking there are useful tones there.

If you are looking for an amp to end all amps, I'm not sure the UV is it. I'd probably buy a modeler if I could only have one amp, just for versatility. (I currently own a Cyber Twin as well as a Marshall JCM 900 and Mesa DC-10.) But as a second amp, or if you want that tube tone, it is hard to beat.

Try the Univalve. You might like it. Don't buy it unless you like it. For under $800, I think it's the best bang for my buck so far this year.

Very staight forward... you can check out the THD website for exact details.

I tested the Univalve with a Tom Anderson Classic and a John Suhr Classic through a Dr. Z Z-Best 1x12 and 2x10. Note... I really wanted this amp because of the portable size, Class A tones, and low wattage. But after at least two hours of testing, I came away very disappointed.

The clean settings had the best sounds. Very Fender-ish to Vox-ish... nice! The distorted settings left me empty. After reading all the reviews below regarding the how the Univalve was able to obtain the plexi-sound, I expected just that. Univalve, in my opinion, did not deliver. The distortion was too buzzy, and I tried adjusting everything to stop the buzz. I tried both my 1x12 and 2x10 cabinets and both guitars, but failed to obtain that silky Marshall driving, plexi sound.

Again, remember, I had every intent in buying and liking this amp, but after playing the Univalve, I just felt it lacked the vibe of the other amps around this price range, like the Dr. Z Carmen Gia.

As with all THD products, this thing looks great and was built to last!

Awesome... always answered my e-mail fast! Customer service par excellence!!

My rating is based on the lack of vibe I got from this amp. Maybe if more of the individuals below wrote more realistic reviews, I would have expected so much from the Univalve. The Dr. Z Carmen Gia certainly does not have the flexibility of the Univalve, but it certainly has more vibe!

The features have been listed elsewhere, but I want to note a few things. I'm one of the converts to this amp(though as mentioned below, the Vox Valvetronix rocks for a modeling amp..I couldn't believe it when I heard it). When I read folks saying the sound sucks, I don't get it. Different strokes I guess. I love the tube switching. The Attitude control is also very cool. Allows you to dial in different attack characteristics. Some people have said it's like presence, but it's not quite to me. It's not just highs, but the attack cut that's affected. Love the tone controls. Two inputs are great. The Rock channel adds the 2nd tube and picks up in gain at the low end of the volume knob where the Roll channel was cranked. High/low wattage switch. Attenuator...All these ways to set up the gain versus volume issue. Below maybe 8db attenuation, the sound changes a lot, but that's to be expected. The post power amp output switchable between inst/line levels is the secret weapon of this amp. That's what makes it so versatile. I've run it to a Mesa 20/20 power amp. It allows the clean sounds to be boosted for much more headroom...awesome. Also allows the cranked sounds to be more quiet...works better than the attenuator, because you're not attenuating the power, just not turning the second amp up. Result...Singing feedback at levels way below what you get even with a 6V6 tube in the Univalve. I couldn't shut up the day I discovered that little trick

I use this thing with a Mexican Thinline Tele(awesome guitar-shocked me), PRS McCarty, PRS thin Hollowbody and a Hamer/Warmoth hybrid strat. I'm into rootsy music...blues, Allmans/Dead, some country, jazz, some rock, Ry Cooder/Lindley, Los Lobos... I don't actively cop people's sounds, but the other day with a 6V6 with the tele of all things through the Rock channel cranked with a Celestion vintage 2-10 loaded cabinet, Duane Allman at the Fillmore East walked into my basement studio. Welcome Duane. With a KT66 power tube the other day I thought Angus Young was gonna jump out of my speaker in his little schoolboy outfit. Yesterday at band practice using an old RCA 6L6 I was able to achieve that one guitar, one cord kinda thing where you turn down a bit for rhythm and crank it for lead thing at about 10 o'clock on the Rock channel. It wouldn't totally clean up with volume, but if can handle a little stuff around the edges. It's not exactly like XYZ when you switch tubes, but the flavors differ greatly. If you're into Mesa quintuple rectifiers and 7 string shake the house buzz cut sounds, stay away. It's not for you.

I've had a hard time getting a good jazz sound from it as it's voices a bit bright. Even with everything rolled off, it's a little bright with my hollow PRS. The PRS has this cut though, so it's partly it's fault. My Blackface Deluxe does the jazz thing a bit better(though I hate to say it, but solid state is good for jazz)

I haven't gigged yet with it. Next week I start a slew of gigs where I'll be using it. I'm gonna take the Mesa 20/20 and a few different power tubes and determine gig by gig how to set it up best. It responds great to OD pedals...I use a Klon and a vintage Rat and they both do their things well.

Ran the direct out straight to my computer recording setup the other day through a Focusrite pre/comp unit. The clean stuff sounded amazing. Rocked stuff needs a speaker emulator I think as the highs get too fizzy. Mark Knopler kinda Fendery clean was awesome though...lots of sparkle, definition and dynamic response. And on and on...I like it.

Who knows. Good reputation. Not much to break.

Again, good reputation. Told Andy Marshall's a good guy by my dealer who's a good guy. Warranty's a year I think.

I've owned Fender blackface Twin, Pro and Deluxe Reverbs(still have 64 Deluxe), a couple of Mesa's, a Matchless Chieftain(great amp, though I just sold it and got the Univalve and a bunch of other stuff), a Hoffman head(cool), Musicman HD120(great amp..LOUD), a Marshall 4203(pawnshop prize..good and compact..watch those highs..OUCH), blah blah...bunches more actually including a custom built 2 6V6 rocking combo. Other than the Matchless which really had it's own thing which I don't hear in the Univalve, the Univalve can get in the neighborhood and often OWN the neighborhood of any of those amps. Been playing since I was 16, 25 years...am I that old? Played in a variety of different band. Total gear hound. Thought about a Carr amp when I bought this. Tried Hammerhead...a little too rocked for me. Damn good amp though. Hear someone play a Slant 6 and thought that sounded amazing. If I'd have wanted to spend $2000 on one gigging amp, that might be it. Tried Valvetronix...awesome modeling...the best I've heard...blows Line6 out of the water. I'd love if it had a buffered effects loop or even if the line/inst out had two outputs so I could run one into a power amp and another into effects. Gotta work out how I'm gonna run effects. Have run reverb into other amp and speaker...sounds great, do I really want to schlep that much stuff? Overall though, it's the most versatile thing I've got. Keep in mind that I'm generally a one channel no bells and whistles kinda guy. I'm not saying it's as versatile at a gig as a Mesa/Bogner/Soldano thing. In the studio it's quite versatile though. I'm a happy camper.

Sounds Ok, but nothing special when considering the price. The tube swapping/attenuator thing is fun - not particularly original - but if everyone wants to give Andy Marshal so much credit for it, then go ahead. Aspen Pitman probably threw up when he got wind of the success of this thing.

I agree with most of the reviews regarding the good combination of clean and dirty tones in one box, but why shouldn't it do that; a lot of amps do. It's a matter of value not raw performance, and on the score the Univalue is very average.

You guys that like this amp are too hard on the ones that don't. If you like, then play it and be happy with it. It's not like you work for the marketing department at THD (or do you?) It's like some of you have never played through and amp before this one.

There are far better values out there. Play a Vox Valvetronix and you'll know what I mean. For the same price you get more tones than a Univalve could ever produce and at a wider volume range.



Returned it.

I am not going to use the standard format here, just a few thoughts and suggestions. I am getting up in years (46), maybe a bit to old to play rock music....but damn, I still love to play my Les Paul every day. I have had Marshalls for the last 20 years or so, and I bought the Univalve thinking I would use it for playing/praticing in my house. Over the years I have always tried to copy the guitar sounds on records, I can come close, but it is never the same. I was so suprised how close I can come to duplicating the recorded sounds of Aerosmith, AC/DC, G'n R' etc using the Univalve. I am using two Ei ECC83's for pre-amp and one old Mullard EL34 "fat base" FX1. I found running on low power actually sounds better to me, hotplate about 11:00, volume at 3:00. I also didn't think the amp would be close to being loud enough for a gig, how wrong I was..... that son of a bitch is loud! I use it through a Marshall 4 X 12 and you would swear it is putting out 40 watts min. Anyways, I am having a ball with it, thanks Andy. My only suggestion would be for someone to put out some plans/prints for a standard wooden amp box, or THD start making them. I feel leery taking it out in the weather with no enclosure to protect it. Over-all... I rate it a solid 9.5

As a follow up to my initial review, I would like to say this.

First off, I too think that this being named anonymous has not given the Univalve its fair chance. I was able to play one of these amps in a rehearsal enviroment for a total of about 4 hours over a a period of two days. Trying different tubes and different cabs, I knew this thing WAS all it is cracked up to be. Thin soundig? About as thin as Rosie O'Donnel at a free buffet. You need to understand one, how the amps EQ including the attitude work in conjuction with eachother, two if you use pedals you are best I think to set thier tone as flat as possible in order to retain the amps EQ settings, three how to use the tone and most importantly the volume on your guitar. These things are crucial with any amp.

As far as getting it to be exactly like a Plex!, well I think its more fair to say that this amp can achieve the best traits of many of the most beloved vintage amps as well as enter into some modern areas, yet at the same time making enhancements to those originals in its own single ended class-A sort of way. To say it is a Fender Deluxe clean or a Marshall Plex! brown sound is only there for comparison, reference you know. However this amp does come frighteningly close to those reference amps used.

I paid $779.00, and feel that I have gotten a fair deal on a terrific product that is backed by the best customer support I have seen in any buisness or trade.

As far as getting one home to find out it sucks. There is NO reason not to fully crank an amp in the store before you buy it. That is part of the customer priviledge. Did you buy your car/truck without test driving it?

The versatility of this amp is perhaps its greatest feature, however that same versatility will yield you with so many other rewards you will begin to wonder how you ever got the amp for just $750.00.

just a quick observation about the univalve - i'm not gonna bother filling in all the boxes. had mine for about a month. i like vintage tones, and usually play a vintage style tele or les paul classic loaded with antiquities into a 2x12 cab w/ celestions. i'm real happy with it. at first i used the svetlana el34 that came with it, but the other guitarist in my band insisted i try an old GE 6v6 i'd pulled out of my champ. i told him it wouldn't be loud enough, but i was wrong. our band isn't the loudest in the world, but our drummer hits pretty hard, and suprisingly the 6v6 (which apparently puts out well under this amp's 15 watt ceiling)is more than holding its own. i don't use the attenuator with it, but keep the volume at about one o'clock. it really is amazing the variety or tones you can get with a good guitar, a tone knob, a volume knob, and a good amp. anyway, the obervation i wanted to make is that i've found that any amp will have good and bad days. whether it's in my head, or something to do with atmospheric conditions, it's always bugged me that amps seem to sound different from day to day. the vox ac10 i was using before the univalve (great amp - now it's safe at home where it belongs) would seem to distort easily one day, and be really loud and clear with no breakup the next. the great thing about the univalve is that if it has a bad day (and it hasn't lately), you just start swapping tubes until the magic reappears. the spare tubes are like whole other amps. and, yes, the tubes make a big difference in the sound. feeling british? put in the el34 ... you get the idea. no doubt, there's a lot of other great amps out there. but the beauty of the univalve is that, unlike other amps which are built around one kind of power tube and require significant modification and expense to modify to another type, the univalve allows you to easily experiment with different sounds - you don't have to commit to just one. i suppose if i had to pick one power tube to use it would be the el84 - looking forward to getting the adaptor so i can slap one in my univalve.

Single ended class-A, treble & bass and attitude controls, selectable speaker ohms, line out, built in noise reduction, built in Hot Plate attenuator, two inputs high and low gain, you can use any combination of 12ax7 compatible preamp tubes and any type of common power amp tubes with out re-biasing the amp. I give the features a 10 because it is all you need to "play" your guitar. You need to know how to control your guitar and control what goes in and what comes out, ie. using the volume on the guitar.
This amp will not lie to you, it will give you what you put into it. You will not be able to hide behind rediculous amounts of pre-amp distortion, patchwork effects loops and fancy switches here.

Signal Path: Amer.Fat strat, Vox wah, Voodoo Lab "Sparkle Drive" "Superfuzz" "Analog Chorus", Guyatone MD3 Delay -> THD Univalve -> Marshall 4x12, Peavey 1x12 w/celestion.

The tones you can achieve are damn near limitless, however you can certainly cop lgitimate tones of our most beloved amps. Here is what I have so far.

EH6v6GT= In the low input a great clean, fat warm and round, very Fender Deluxe. In the high input a bit of the same with that Deluxe cranked at about 8 giving a butter churn thick overdrive.

EL34= Look out! This is definately brit tone and fantastic at that. You can get some really great cleans and brit blues crunch, but there is certain Plex! brown_sound here, you can easily cop a terrific Slash tone or early EVH.

5881= This could be my favorite, I dunno yet. On the low input you can cop some of the same as the 6v6, but with more headroom and volume of course and turn the volume up to about 3:00-4:00 and you get a blues overdrive very much inside of Bassman territory.

On the high input you can get warm round cleans, overdrive/crunch and into some pretty high gain that is easily sufficient even for most hard rock and metal.

I will keep experimenting with different tubes, and allthough I have made representations to some very well known popular amps, let me say this in conclusion to these claims. This amp is not a Fender Deluxe, Bassman or Plexi, but what this amp does is it exhibits the best traits of those beloved amps in a single ended class-A circuit there by enhancing the sounds of those amps with harmonic detail and clarity that those amps normally were not known to achieve. If you say you cant find a good tone, you're lying to yourself or have'nt matured into real tone yet, I went through the same thing too.

I have owned Marshall(TSL) Mesa Dual Recto, and fender and peavey and feel quite justified giving this a ten.

Built to outlast the next millenium. The customer support at THD is unparalleled. THE BEST!!! These guys really want to help you and your experience with thier product. They want to know about you and the amp together.

As mentioned above, sorry.

I have never given any product all tens and am questioning myself right now. Am I nuts? No, this amp is the nuts, its really that good and you owe it to yourself to try one if you get the chance to. I would like to have a second one so I could have one set for each of the low and high inputs and A/B them in my cab. But stolen...He better run faster than a bullet, then I would buy another one.

We all know every feature of the amp, so I'll skip this section.

I have to tell you, I jumped on the Univalve bandwagon and ran out and bought one. I am somewhat dissapointed, not all its cracked up to be. It is OK for a pratice amp... but $750.00 can go a lot further if you shop around. Anyways, I sold it after two weeks and went back to my good old 2204. And BTW, anyone who says a Univalve sounds like a plexi is in dream world....I have a 69' to compare it to.

Seems well built but I have some issues about the price. Lets take the aluminum face plate they say is so cool. It's a nickles worth of material and any good CNC programmer could duplicate the program to make them in 2 hours. Then we have $75.00 for transformers, pots and 3 tube sockets. Add another $25 for extra crap and what do you have? You tell me. The most expensive item on the amp is the steel cover, very well made and also hard to make from a machining standpoint (and I have been a machinist for over 25 years).

The dealer near me was a arroogant ass to put it bluntly. THD has cut several dealers so the remaining few can jack the hell out of the price.

It would be a cool amp for $300.00 but for the money... use your head guys. I know, I know some of you will ball and cry about this review but let me finish by saying before you buy one.... try one out at your house for a few days with a few other amps also and tell me with a straight face the Unvialve is worth that much. And unlike some other reviews I "dare" to put my email even if I will get bombarded with hate mail from Univale owners (who are stuck with a $750.00 toy)

FOREWORD: I've had this amp for quite a few weeks, and have waited until I've rehearsed/gigged with it a few times before I posted the review. I'm happy to say, I'm still as pleased with the amp as when I've first played through it in the store - fifteen minutes before I bought the thing. :) Get ready folks, this is a long review - but I did try to add titles to each section, so you can skip around if you'd like.

SETUP: Ibanez JS1000 -> Pedals -> UV -> Avatar 2x12 with Greenbacks. Pedals include: Valvulator Buffer, Crybaby, Ernie Ball Volume, DOD Milk Box Compressor, MXR Phase 90, Ibanez DE7 Delay.

MORE ON SETUP: The UV will sound quite different depending on the tubes being used. Personally, I like the Svetlana 6L6 the best - really tight and focused distortion. I also swapped out the 12AX7 in the driver side of the preamp tubes, and put in a 12AT7 for a slightly lower gain setting. It's still got plenty of gain, but less compressed. Speaker wise, I chose greenbacks, since they seem to compliment the UV's sound best, for my type of sound anyway. I tried the V30s at first, which gives a very defined and clear sound. The greenbacks, however, gives a warmer and rounder tone.

FEATURES: This is the cool thing about the amp - on one hand, it's a beautifully simple design, with very few knobs and switches; but on the other, it's got tons of very cool features.

Low wattage & built in attenuator - VERY cool. A must for good cranked tube tone at low volume, EVEN FOR THIS 15 WATTER. More about this in next section.

The built in noise gate - also cool.

Built in dummy load - VERY smart. No risk of blowing the head in case the cab isn't connected properly.

Selectable cab ohm rating - very convenient.

Ability to swap tubes - well, need to say more?

The issue of no channel switching - well, you can't channel switch, nor can you plug into both inputs and use an A/B box. But I don't find that a problem at all. By default, I plug into the "Rock" channel, and simply turn down the guitar volume to get a clean/semi-dirty sound. Works well. Works even better with a compressor for the clean sound, for my applications anyway.

The issue of no effects loop - When running the UV clean, you can just put the effects in front of the amp, and it'll sound about the same as if it's in the effects loop. But for the distorted tone, stuff like chorus, phase, and delay will sound a bit muddy when running in front of the amp. This seems like a bummer at first, and it is - but that's the nature of ANY cranked tube amp. Even if an effects loop is built into the UV, the fact that you're cranking the tube will defeat the purpose of the effects loop. The only way you'll be able to get, say, good distorted tone with clean delay, is by either adding the effects at the sound board, or by slaving the UV into another amp. Again, this isn't the UV's design flaw, but just the nature of ANY cranked tube amp. Kinda just have to live with it. Which is why I'm still giving the UV a 10 on the features.

ON TONE: The tone coming out of this baby is just unreal. Pure tube distortion at its best. Not the Boogie/Recto type of distortion, mind you, but the classic rock type of sound. It's in the Marshall/early Van Halen ball park, but at the same time having its own distinct personallity. The UV has more bite than any Marshall that I've ever heard, and cuts thru the mix VERY well.

MORE ON TONE: This amp DOES sound brighter than most amps I've played. I really appreciate it, actually, because that allows it to cut through the mix like no other. If you do any kind of gigs in a band, you would know that it's not about how good an amp sounds by itself, but how good it sounds IN THE MIX. However, I did notice a bit of high end sizzle, when I first bought the amp. That disturbed me at first, and Ed from THD explained to me, that this is due to the amp's design. The amp is designed to sound bright and clear, so even when distorted the tone doesn't get muddy - result is a very bright tone with a bit of high end sizzle when used with certain tubes. Well, once I switched from V30s to Greenbacks, that problem was neutralized.

ON VOLUME: After having gigged with the amp, I will now forever sneer at ANYONE who tells me that they NEED the firepower of their 100 watt Marshall head into a 4x12. The whole power/volume thing is just so over blown. I mean, the UV is 15 watts, and I'm running it into a 2x12 with Greenbacks. During the last gig, which seated 100, but can easily seat over 200, I can be easily heard over our raging drummer and bassist, unmic'ed, with attenuator at 1/2 the max power. Actually, the sound guys kept telling me to turn it DOWN during the set. I did choose to mic the cab, as I always do, to get a more consistent sound out to the audience. When I practice at home, even with the attenuator at about 1/2 power, the neighbors across the street can EASILY hear my amp, during the day, with all windows/doors closed. Believe me, this amp is loud enough for small/medium gigs without being mic'ed. If you ever need more volume for large gigs, you can always go through the PA. I mean, the PA is there for a reason.

MORE ON VOLUME - If you ever find yourself cranking the UV at max power, and you still can't hear yourself, I say FIRE YOUR DRUMMER, or bassist, whoever is louder. If you're playing at that kind of volume, chances are, you're gonna be too loud for most of your gigs, and are definitely gonna be asked to be turned down by the sound guys.

ON VERY-LOW VOLUME SETTINGS - Some folks are dissin the amp because it doesn't yield a good sound at speaking levels. I hate to break it to ya, but you won't get decent distortions at speaking volume with ANY amp. The problem, is that guitar speakers are designed to work best at higher volumes. At speaking level, ANY distortion will sound buzzy and weak. Good speaker break up at higher volumes, which contribues a lot to the distorted sound. For those that claim the UV is buzzy at even high volumes, I'd say that either something is not right in your setup, or their idea of a good tone is...well, VERY Different from most people's. I'll just leave it at that.

Don't let its cute look deceive you, this baby is built like a tank. The PCB used is the thickest I've ever seen, and all the solder joints are done nicely. The nice thing about the amp, is that you only need to bring ONE spare power tube to gigs, instead of two, four, or six on some amps. It's also got 3 fuses for protection. Very well made amp, the price tag is a steal.

Chatted with Ed DeGenaro a few times, and the guy is not only knowledgeable, but friendly as well. In fact, if you hang out at the Harmony Central Amp Forum, you'll run into Ed here and there. He's a regular poster there, far before the UV days. Excellent customer support.

I've been playin for about 6 years, and been giggin regularly for the past 3, 4 years. I've gone through a fair share of amps, even the modeling stuff. This is by far the best tone I've ever gotten out of my rig. It's simply top notched. And as I said, the price is a steal, for an amp of this caliber.

Lastly, a disclaimer is needed here: Hard rock is my cup of tea. I love the tone of folks like Van Halen, AC/DC, Satriani...etc. My opinions are based on my likes and dislikes. By all means, try out the amp, but make the decision to buy/not buy base on your own taste. But honestly, I find it hard to believe that anyone who has any appreciation for quality tube distortion would dislike this amp.

Hmmm.....I wanted to post this comment. I wonder if something was wrong with "anonymous'" amp? Why bash the guy and assume he's just flaming the THD? If the guy says it sounded thin, most likely there was something wrong with it. We all know that this amp is not thin what-so-ever. Mine kicks the big "A" even at low volumes. It does sound thin with the Hot Plate below the 9 o' clock position. This is pretty low volume. Maybe anononymous was looking for something that sounded fatter at even lower volumes. Good luck. At 9 o'clock and above, my THD sounds awesome. I'm using good NOS tubes though. If "anon" still has it, I highly recommend a philips ECG83/12ax7 in the input, a GE 5 star 12au7 in the driver, and a philips 6L6 in the output. Mine absolutely move air at very low volumes. The string pluck is INCREDIBLE. The notes "snap" and punch right out of the speakers with authority. Think of old Billy Gibbons on steriods. I also use a Scotts Crispy Creme Treble booster at times. This is a very luscious tone, reminescent of Brian May. Personally, I think "anon's" tubes were bad. Bad tubes (which is common now-a-days)always sound weak and thin. Oh well....

See below

The clean is very warm and nice sounding, the overdive is flat and thin. Sorry, I just didn't care for the amp, I sold it within a week. I bought it based on the THD website and reviews here, unfortunately I couldn't try one out in person since they were hard to come by. This amp doesn't live up to the hype. Learned my lesson.

Finally, why do people get so defensive about reviews that aren't positive? If you love this amp, good for you! Don't go around bashing people if they don't agree with you. This amp is good for some people and their styles of music, but it is not the holy grail of all amps. The THD website misleads people saying this amp goes from clean to high gain, with the ability to hear "complex" chords while heavily overdriven, absolutely not true. Oh well, if you are intrigued by all the positive reviews on the site, go check it out for yourself, it just may be what you are looking for, but maybe not. Have a nice day!

Already listed.. Had all I was looking for versatility around a SIMPLE concept. Ability to switch tubes for me was perfect( I do a lot of recording) within the character of the of you can get shades of Fender, Vox, Marshall. I got this a week ago, wanted to wait to post this until I put it through it's paces.

I play Musicman Silouettes all (3) with stock singles in the neck and middle, Duncan JB Jr in the bridge ( but angled backwards- high end towards neck, low end towards bridge- ala Dick Dale).

I play instumental metal, but I hate a buzzy type distortion so I was looking for a vintage Marshall type of vibe... This definitely does that for me. The amp is quiet, although I have been running it without the hotplate, without the noise reduction, at FULL volume with a Voodoo Labs overdrive ( the old style, set mainly as a clean boost with just a bit of gain for sustain ), but noise to signal ratio is fine.

So far I have found the best sound using a 6v6 ( which suprised me to be honest, tried 6550,el34,6l6, and kt66 as well ) but I still will be hunting for more tones out there.

I think the clean channel is great, but I have been useing the rock channel and just controling my gain with guitar and pedal, this works very well.

This amp doesn't have " BRUTAL " type of gain, but I am getting a VERY heavy tone..SWEET!!

Just got it, but it is built tough as hell, I have opened it up already. I am giving it a 10 because I used to build amps.. This one should last like the energizer bunny.

I got home with the amp it did not work when I switched out the tubes... Called and Andy ( the designer of the amp! ) talked me through finding a small cold solder joint on one of the sockets... Works perfect now. This blew me away, this call was on a SUNDAY!! Andy ( and everyone else there too) just reek killer customer service. Kudos!! Actually I give them an 11, beyond any resonable call of duty.

I have been playing 22 years and have owned or played though all of the big names stuff ( some small ones too). I plan on buying a second one to switch sounds with.. So yep I would buy it again ( after I hunted down the person who stole it !!)

It does what I was looking for perfectly... Nuff said!

Seems to be a very straight forward head but there are a lot of neat little features. Two inputs, for different gains, volume (adjusts overall gain), treble (very responsive), bass (can't tell too much difference until it's cranked up), attitude (adds some high end along with sizzle to the gain), Hotplate, Hi voltage-Low voltage switch, Noise reduction (useless, as this amp is very quiet without it), and a line out.

I'm using single coils and humbuckers with this amp. The Roll channel emits sounds from sparkly clean to a nice vintage Marshall purr, ala Hendrix. The sound of each individual guitar really shines through on this channel. The clean sound, IMO, is a cross between a Vox and Fender. You can mess with the controls for days and keep finding new variations.

The Rock channel picks up from the Roll channel and goes into a pretty searing overdrive. It's all still Vintage Marshall sound. It's not bass heavy, but there's more than enough treble to cut through. The Attitude control adds some high end to the tone, much like a presence control but more musical, and also adds a little more sizzle to the overall gain. Turn it down and it smooths out and isn't quite as aggressive.

A lot of guys might be wondering what kind of sound it gets. I think it's more like an early AC/DC tone. But it can also do more than that depending on the way you play. It's very useable. A problem I have with the Rock channel is it's not very responsive to the different pickup settings on a Strat when it's set to high gain. Mainly, just the lead and neck pickup are useful. That's one thing I like about my TriAxis. No matter where my pickup selector is set, you can here it even with high gain.

I've tried different power tubes and I'll tell you, I can't hear much difference. I think there is a lot of hype around this feature, but I haven't gotten great results. An EL-34 will compress more than a 6L6, but the tone is basically the same. I haven't tried an EL-84, so I can't comment on that one. I've tried some different preamp tubes with more desirable results. A 12AT7 is mellower than an AX7. One guy said that he can get any distortion sound with this amp he's ever heard recorded. Give me a break! What a silly thing to say. This amp does a few things and it does them very very well, but it doesn't do everything.

One thing I will say, the more I play it, the better it seems to sound. Maybe it's the tubes breaking in but it does get better. Also, this amp will NOT hide sloppy playing. If you're a weak player, it will show it, but if you stay with this kind of amp, you will have to become a better player in time or go back to your Recto's.

I tried running the direct out into my Mesa 2:90 poweramp and it definitely sounded different. I think a solid state poweramp may achieve better results since the tone generated is at the amp and another tube poweramp will only color the sound even more. I don't have a SS poweramp so I can't testify for sure.

As far as the Hi Lo Voltage switch, I don't hear much, if any, difference there. I'm sure there's some psycho-babble-technical explaination there, but it means nothing to me.

Overall, this is a very unique and fine amp. There are no ugly harmonic overtones whatsoever as with most class A/B amps. What you put in, comes out.

Haven't gigged with it but it seems to be built like a tank.

Haven't dealt with them but I've heard positive things about them.

I've been playing for 22 years. I started out on a Kustom amp, then to an ADA MP-1, about every Boogie out there, Fenders, you name it. This is a great amp and for what it does, I give it a 9. But it's not everything like people are making this out to be. People are going ga ga over it as if it were made of gold. Don't get caught up in the hype, try it out for yourself first.

It's very sensitive as to what speakers you use, poweramp for slaving, etc. It's very versatile in the classic sense of an amp, but it's not the end all of amps. For the money, you can't beat it. Keep in mind, everyone's perception of great tone and sound is different. I won't slag any amp just because I don't like it, but you need to try it out for yourself before you buy. It gets great tones for me but it definitely is not the only amp I can get by on.

I'll probably get flamed for some of the things I said here, but who cares? Some of these guys need to grow up and quit acting like they found the end of the rainbow.

This is an answer to "Anonymous". Did you guys noticed that the only negative reviews of the THD are coming from one (or more, but I think it's the same guy) courageously hidden behind this "anonymous" thing?
I hereby ask Harmony-central webadmins to allow the right to post reviews to the only ones who give a name and an email - it is just too easy for any wanker to put the blame on a product they just don't know.
A valve amp that sound thin and lifeless at low volume? Of course, they ALL does! No ability to reach a good sound at room volume? Of course, if you've just tried it with the stock valves! Did you tried 6V6 or EL84? I bet not.
And with which speaker did you tried it? Only with the one of your Deluxe? Don't you know that the sensitivity of a speaker is one of the main influence on the perceptible volume? Did you ever heard the huge difference between a speaker rated at 95 dB and another at 100dB ?
And all this to allow you to put a miserable 3 as rating! or did you just mention your IQ there?
I have nothing to do with THD, but I'm really angry to see such a great product criticized by anonymous ignorants.

Just wanted to "chime" in on the subject of using the Univalve in very low volume applications. If, after reading the reviews on Harmony Central, in addition to the user's manual, you've got visions of using a Univalve to produce output tube distortion at speaking levels - then FORGET IT. I'm trying to save you $800 and the hassle of setting one up for this application only to find out, like I did, that it is quite fizzy and thin at speaking volumes with the volume above 1:00 and the attenuator set to where the amp doesn't rip your head off. Since the literature on this amp describes several ways in which it can be configured to achieve a high gain (power amp) tone at a low volume, the natural assumption would be that it would sound good when doing so. I didn't find that to be the case. The Univalve allows its line out to go to a slave guitar amp or to a speaker (using the speaker out and the built in hot plate). Not only does the tone suffer when the attenuator is set below 12:00 the power tube emits an audible buzz when the amp is turned way up yet attenuated to speaking volumes. (Note that it is not the fault of the Univalve that this happens. Plug any amp into a dummy load, turn it up all of the way, hit a chord, and buzz on dude.) If everyone reading this is thinking: no amp is going to sound good in that situation, then read some of the Hot Plate reviews and you'll find that others have attempted the same application with Marshall heads and what not and had the same complaint.

Don't get me wrong, this is a high quality innovative amp capable of many tones via tube swaps and tweeking. In fact, when plugged into the speaker in my (real) '65 Deluxe Reverb, the amp produced beautiful clean tones that sounded as good as the Deluxe itself. The high gain tones are great too, but only at fairly high volume levels. I do think that the tube swap mania surrounding this amp, according to the reviews, are over-blown. Yes, there are slight differences when swapping between different power tub types, but sheesh, calm down already.

See amptone.com for more info on low volume applications. My personal favorite is a SansAmp Classic that I bought 10 years ago plugged into the low input of my Deluxe Reverb. Set up right, it produces an overdrive tone that is almost dead on, at low volume, with no noise.

I give it a 3 for low volume applications, give it whatever rating you want when used in high volume applications.

Well built.

The guys at THD are very good. When I asked about the tube buzz thing someone at THD siad "oh, yea it will do that".

Features listed in previous posts. If you consider the purpose of this amp (output tube saturation at low dB) the features are tremendous and well conceived. If I was in a rock'n'roll band right now, this would be all I need. I'm doing old school funk and need a Twin clean tone and crunch, so I wish there was a way to A/B the two channels.

I have a Warmoth Strat with Rio humbucker and 2 Fralins, a Legacy with Tone Zone and Fralins and a Fender Esprit (Japanese version of the Robben Ford Signature) with Fralin humbuckers. All sound great with this amp. As mentioned below, it can produce an extremely wide variety of tones. I've only scratched the surface re: swapping tubes--haven't started my NOS journey yet. All I have are a Yellow Jacket/EL84, and current production 6L6s (GT blue and white), a GT 6550, and the Svet EL34 that came with it. I've tried a few new 12AX7s...EH, Ei, JJ Tesla. My favorite (SO FAR) is EH and 6550, Rock channel, volume at about 10 o'clock, treble at 12 o'clock, bass 12 to 3 o'clock, attitude 12 to all the way up, Hot Plate at 12 to 3, and in the Low V position. I'm using this with a Jenkins 1-15 cab and a Jenkins 2-12 (I'm looking into starting a cabinet collection to go with my future tube collection). This gives a decent AC/DC crunch and I use a Sparkle Drive to clean boost it into fat, singing solo sounds. Phenomenal...It's the most fun I've had playing guitar in recent years! The YJ with EL84 is WAY COOL as well...very Brian May. I tried using the Roll channel with a couple of different distortions (Guv'nor and a Line 6 distortion modeler)--they sound ok, but are pure crap compared to the Rock channel. I've talked to a couple of guys that use one UniValve for clean and another for crunch, and must say that it sounds like the perfect rig, if you disregard the expense.

The other concern for me is that I work in a 10 piece funk band, and might run into problems getting sound guys to burn 2 channels for guitar. I've considered switching at the output, since the UV has a dummy load (you can run it with no speaker plugged in, ie for recording from the line out), but don't know if that would work without popping.

I bought this because it has tones I haven't had since I sold my big Marshalls years ago. I play a Twin now (on 2-1/2!), and that's definitely the right amp for all the clean tones in this funk band, but I want to build a smaller more portable and versatile rig. The Univalve is, WITHOUT DOUBT, going to be the core of that rig. I just need to work out a way to get the Roll channel at 3 o'clock and the Rock channel as described above. Suggestions? email me!

Seems really well built. I've had it several months...no problems!

Ed put up with a few stupid emails from me when I first got it. He was informative and quick with information.

It simply rocks. Buy one. You won't regret it.

Features detailed in previous reviews. Key for me was getting true power tube distortion, for a variety of tubes, at lower volumes. As far as I know, this is the only product in the world that does this. Channel switching would be a very nice addition, but I did not consider it necessary, as I have a sperate amp for my main clean tone.

I have searched for years to find distortion tones I liked at low to medium volumes. I play mostly in smaller spaces, and I think most bands play to loudly anyway. Clearly a Marshall 1959 stack dimed was not an option for me. Even a Super Reverb topped out is a little much. With my different cabs, I can now get pretty much the sounds of either (and a lot more besides) at almost any volume. Admittedly, you will need a 10 to 15 Watt speaker to get speaker break up, but I am happier with my overdrive-distortion tones than I have ever been. Untill someone can really put tube tone on a chip (tried the Cyber Twin and the ZenTerra - close but no cigar) the Univalve is it for me.
Guitars: Yamaha SA2200(ES335), Strat/Fralins, Hamer Newport, Charvette/Dimarzio VV and SD Pearly Gates.
Style: I like it for all my overdrive sounds - 60s - 80s rock & pop styles, no effects. I use a 65 Deluxe Reverb with a Weber speaker and a 2X10 extention cab for cleaner surf to blues with reverb.
Noisy: Very quiet, even with the noise reduction disengaged
Variety: No other tube amp comes close. I have run a Mullard EL34 with a Mullard ECC83 in the drive socket and it's all Late 60's London! Yeah, Baby!
Clean Channel: Is designed to overdrive at the top
Brutal?: It will produce higher gain than any classic one channel marshall, but it is not an extremely bottom heavy amp - However, with One 15 to 30 Watt 12" alnico speaker, a pair of crunchy 12ax7 pre-amp tubes, and a 6550 power tube, you can probably get pretty deep into currently popular metal and alternative tones.

It seams very dependable. I have not yet travelled with it yet.

Truely outstanding. Ed DeGenaro has called me back on their dime several times and used e-mail to answer all my questions in less than one day!.

I took my first guitar lesson in 1963.
I own the electrics listed above, plus a seagull grand acoustic.
Deluxe Reverb, Yamaha T100, 2x10 Jenkins cab, 2x12 Jenkins cab. Fender champ.
It gives me exactly what I have been looking for, so I am very happy.
I played many boutique amps, Bogner, Koch, Budda, Victoria, Engle, Guytron, etc. almost all the modelling amps, and all the standards (vox, marshall,mesa-boggie, etc. Some great amps there, but the Univalve is the only one that has the tone I want at the (lower)volume I need. Channel switching would help in live gigs.
It would be nice if it had a built-in spring reverb, but that would make it a lot bigger, and it's small size is a great plus.

Plenty of versatility. Love switching the tubes in and out for instant comparison. thd has the Univalve owners manual on their website.

True Tone music in Santa Monica, CA is a great store. I have bought a bunch of stuff there.

http://www.truetonemusic.com/index.html
phone: 310.393.8232

Strat, Les Paul, Grosh, Anderson, Tylers. A very expressive amp - responds well to each guitar. Tried various El34, 6L6, 6V6 (low voltage setting only), all sound good, prefer the 6L6 for overall versatility.

Loud for 15 watts, similar to a Blackface Deluxe.

Incredibly well built. Love the pop off lid. 3-fuse protection. I have a bunch of Hot Plates and all their stuff is solid. The website says they will make interchangeable cabs/combos.

Never had an issue, everyone I know who has talked to the guys there say they are great.

It is a great idea done well. An excellent addition to any player's amp collection.

Number 545 made (2001). You already know the features.

I've tried the UV with various 4x12's, 4x10's, 2x12's and 1x12 cabinets and I seem to settle on the 1x12 (w/ V30). Maybe it's just the mini-Marshall look... The amp is surprisingly versatile. The Roll channel isn't exactly Fender like but it has a servicable if not exactly loud tone. The Rock channel is really what this amp is all about; turn it up and get feedback and sustain that under normal circumstances would make your ears bleed. REALLY cool. Don't think I would gig with it but it SMOKES for getting a cranked volume in a recording situation.

Clean, sturdy, "boutique" like build quality. The amp does use PCB's but they are neatly laid out and the components are first rate. Look for the quotes, pretty funny stuff...

THD has always had a good rep. I've owned HotPlates, Yellow Jackets, etc.. and they've always been well behaved and well engineeered.

For what this amp is designed to do, I do not think it could be improved upon. It is wildly flexible, sounds incredible and has that intangible mojo that makes owning high end guitar toys so fun. If you need a flexible, low power tone machine you should check this amp out. I also highly recommend Main Street Music in Utah as a place to get this amp (http://www.mainmusic.com) as they carry all the fun toys and have exceptional service. I called Mike up, they had 2 in stock and boom I was playing my Univalve.

As an aside, after going through just about every major amp and guitar over the last 20 years, I'd have to say that my top 3 amps are the Mesa Boogie Rectoverb, Fender Super Reverb and the THD Univalve. There are other great amps out there but if you can't find good tone in this group of amps then it may not be your equipment...

Another random comment: does anyone make a "kit" with 1/ea of the tubes the UniValve will use, an oven mitt and a nice wood display rack? Seems like THD or Lord Valve or Mike Kropotkin would make a killing on these. Can you imagine; a YellowJacket YJUni w/ EL84, a Mullard EL34 an RCA Blackplate 6L6 a Telefunken, uh yeah... Shoot, they don't even have to be matched tubes with this amp! Someone lemme know if there already is such a thing.

For what the amp was intended to be, the features are great. It keeps tweakers from ruining their sound and allows amatuers to get a great tone quickly.

I've used the amp with a stock Strat with Lindy Fralin pickups and also an ES335 reissue. With the 335 this thing does an amazing Dumble impersonation....nails the expressive Carlton/Robben Ford thing on the "clean" channel wide open. Stick a tube screamer or a Fulldrive in front of it and you're good to go! With the Strat you can get a great Texas Blues vibe...the character of each guitar really shines through on this amp. I have old Marshalls, a '64 blackface Deluxe, a Naylor, a Matchless, and VHT gear and for my last couple of gigs I used the Univalve with a 2x12 dry and took the line out through a Memory Man into a 50 watt Marshall power section into a 4x12 with green back 25s and it was scary good tone! I used the clean channel (Roll) wide open with a Fulldrive II pedal in front and the Memory Man set for a little slap...very cool. The "Rock" or dirty channel is suprisingly versatile...you can dial it back and get sort of a Vox or Matchless type sound or crank it up and get modded Marshall type over the top stuff. Can't say enough about it....money aside, amazing tone.

So far no problems. THD has a great reputation for quality.

I've spoken to Andy a few times...the man is very passionate about what he's doing. All at THD are very helpful.

I've been playing for 30 years and professionally for 10 and I've already stated other gear that I own. I may have to buy two of these 'cause I like it so much.

Just in response to the review below. Effects loops are placed between the preamp and power amp. Most of this amps distortion is from the power amp. You DON"T want to run effects before a distorted power amp, it will sound like crap. That's why this amp doesn't have an effects loop, but a line out. I'd recommend getting a seperate power amp, run the THD's line out into an effects processor (a mono to stereo effects processor works well), then into the power amp. I've tried it and its killer.

2001, I think. Two channels (not switchable). Volume, Treble, Bass and Attitude controls. All dials will affect each other for the total sound. Built in (switchable) powersoak and noisereducer. Level adjustable line-out for recording or slave. The amp has not an effect-loop, but gets a 10 because the features are all useable, inventive and really work extremely well together. And the possibility to easy apply so many common tubes with no bias adjustment, well that is versatility ! It has not enough power for all my needs, for that I have a Mesa Simulclass 295. I bought it as a practice amp for low volume situations. The low power single ended design trades power for quiet operation, clarity, warmth and realism. Exactly what I wanted ...and got.

The amp sounds great. Plenty of tone. Advise: Use closed box for good bass control due to limited power. Use Alnico speaker(s) (if you can afford). Heavy ceramic speakers usually want loads of power to work properly (even though the sensitivity is high, i.e. vintage 30)

I use Gibson Les Paul Customs with both Seymour Duncan and stock humbuckers. Both sound great. But beware ! The input gain capacity on the Rock channel is limited. Plug in an active EMG-81 and the sound is harsh before 9 o`clock volume level (volume on guitar pegged). Roll channel worked very well with EMG-81. Very little noise even with noise reducer off. The cleans cannot possibly get warmer and dreamier than this. Recommended ! No distortion other than valve compression from volume one o`clock. I get really good distinct crunch sounds as well, straight out of the amp, that is, especially with the EL-84 yellowjacket coversion. Not enough bottom end and power for new metal stuff, but it covers almost anything else I can think of, and it does it perfectly. Sound quality is simply amazing.

Had it for only 3 months. No problem. Only sounds better. (Probably me getting to know the amp.)

Extremely good service. When I ask THD something, I usually get the answer within 10 minutes. This make me feel safe. A clear 10.

Been playing for 10 years. Also own a Mesa Boogie Simulclass 295 (endless crunch) Use Gibson Les Pauls. I would by it again, if I still can find one. Have been trough a lot of different gear, but no amp I know can offer this kind of quality and versatility ...at this price, at least.
Highly Recommended as a practice amp ! It is a pleasure to play.

The other reviewers are much better at pointing out the Univalve's technical merits, I'm just disappointed that it does not have an effects loop.

My two main guitars are a Hamer Newport Pro w/Seth Lover humbuckers and a Gibson Les Paul Special with P-100's. It really makes both of these guitars sound great!! This amp was purchased for three reasons: 1. To have a lightweight small rig, 2. To have something flexible for recording purposes, 3. I wanted a good practice amp. The Univalve really exceeded my expectations for all three purposes. You can definetly do gigs with this baby, use a 2x12 or 4x12 and you are so vegas !! Unless you have the freedom to play VERY LOUD the Univalve plays at a very friendly club level, a little positioning and a 57 go a long way. My preference of tube choices for gigging would be a Ruby or Svetlana 6550 and two JAN Phillips 12at7's, using this in conjunction with a 2x12 with Vintage 30's does the trick for me...dare I say gorgeous guitar tones that make me very excited about playing!! WOA M*THERF*CKER!! For recording anything goes, I have tried 6L6's, EL 34's, 12ax7's and 12au7's. All combos sounded good-great, and recording with this amp is fun. Don't forget your Roll input, this is more pertinent for recording and practicing. I should also point out that I use a Fulldrive 2 for the clean boost option with EXCELLENT results, a little more volume, a little more crunch!! TASTY!! My other amp is a Fender Vibro-King. It is a wonderful amp, but it will definitely be hanging around the house a lot more now. The Univalve will be my preference when gigging unless I need lots of volume. The power attenuater really comes in handy for me when practicing late while the family sleeps.

I think it will be VERY reliable. I don't think it will fall down a flight of stairs as well as some other amps, but it definitely is built Ford Tough. I've only had it for 3-4 months.

My order kind of got lost and to make a long story short, they were very helpful and concerned in rectifying my situation fairly. You can tell when speaking with them they are passionate and proud of their products. Nice folks, I look forward to making more purchases in the future.

I have been playing 15 years or so and I have tried and owned many quality peices of gear. The price/performance ratio here is really overwhelming. My hunch is that the Univalve will be spoken of very well sometime soon by some guitar magazine and I will be very happy I already have one. I know Andy Marshall has had geat success with some very innovative products, but my guess is greater things lie ahead for THD. Price/Performance-wise this is my best NEW musical purchase ever!!

made in 2001; it is a very versatile piece of gear,all this stuff has been written about already. it's a two-channel amp,albeit one channel at a time is available. no loop,but the wet/dry setup is the real way to go. i wish i could switch channels..i'll probably get another one when i get some dough..i use every feature. i use it at home mainly, but i just got it yesterday...give me time and i'll work it in to everything,i'll bet...cause it's a great tool when used properly.enough power,you ask? you can either slave it to apower amp,or run into the front end of something like a marshall. or;here's a revolutionary concept: you could mike it.

i use a 1969 strat with kinmans,a custom shop les paul with 57 classics,another strat with kinmans,and a heritage h-150 with gibson 490 neck and gibson 57 classic bridge.each guitar sounds like itself..oh yeah..i have heard that guys don't care for el-34s in the output section, but guess what! if you don't dime every control,you can sound like anything you want with el-34s. i get the feeling that these amps will become a modern classic,so learn this amp. turn the volume up to get your desired gain,and turn the tone controls to zero. then shape your sound. it's no crime to turn your bass off,treble on 2 and attitude to 3 if it sounds as glorious as mine does when i do that. i tried a sovtek 6l6 in it, and it sounds like whatever neal schon used on "when the lights go out in the city"or wtf it's called. with the supplied e-h el-34 billy gibbons,ritchie blackmore,jimi,and beck-ola are all in plain view. at realistic living room volume. why anyone would waste money on a digital snapshot of the above is stupifying...when the real thing is within reach for the same money. my style is like that mutt you see walking up the street...everything. considering what you get,noise is extremely low..but,heyy....i use kinmans,baybee. obviously the sounds it can make are beyond my reckoning,since you can swap input tubes,driver tubes and output tubes.the clean channel will not distort unless it's hit very hard.that's just what i want from a clean channel.is the distortion brutal? hmmmm. using a ebmm-type guitar,i got randy rhodes, edward the great,and joe satch..is that brutal enuf for your ass? remember...star with the volume control; dont just turn everything to 10.there's a lot in there.

i just got it yesterday,so i cant speak for reliability...but it looks numbskull-proof to me. i'll send an additional review in 6 months. but by then,of course,you'll have one.and you know you will.

i only dealt with guitar resurrection,who honored a price of $759, even tho the price went up $29 in the interim..great stuff..

been playing professionally since age 12..i'm 46 now..i own 2 blues juniors,which sound good with a little help,(h+k tubeman,hot cake, teese rmc1,whammy2, zoom choir)...i don't want to contemplate what i'd do to the mug that stole it. i'm getting another anyway,cause it's that good.what i love about it is the tone(s),the fact that it can nail those tones at almost any volume is almost an afterthought. i wish it had the ability to reproduce itself. one other thing i'd like to share:jimi hendrix would have 2.
peace

This amp is the simple complicated unique example of very inventive thinking on the part of it's designer, I'll let the other give the details, I like the simplicity of it's flexibilty

After trying 4 different EL34's, a 6L6, and a 6V6 I'm very surprised by the nuances of tone that can be acheived, I'm looking forward to other tube types, I have alot of 12AX7 type preamp tubes and have tried them all, that was a real adventure, from WXT grind to nuemann high fidelity this amp produced wonderful tone of all types, you really find out what tones these tubes were meant to produce,

After blowing the 1/4 amp fuse a few times with a couple of bad power tubes I e-mailed THD and got immediate response, other than that there have been no problems, this amp is structurally strong and electronically sound supported by great customer service

this is a breath of fresh air and the combination of a quality product and friendly service right up there with Rivera my other amp head

I've been playing gig's since 1967 and enjoy good gear and have owned all the major brands of amps and guitars plus some of the strange and not quite normal, a gear head of the 10th degree, I've seen played and owned just about all and when something like this little amp head comes along it's all seams worth it.

I would have to categorize this amp as a tone generator. It's extremely versatile with it's ability to accept a multitude of power and preamp tubes. Because of this, it is capable of producing a wide array of tones and gain structures albeit one at a time. It has two channels but they are not switchable.One channel is very clean with high headroom (Roll.) The second channel has tons of gain and sustain (Rock.) The other feature are a passive noise reduction switch, built in power attenuator, full power switch, hi-lo voltage switch(Variac), variable line out and impedance selector. Oh and a really long power cable.(yes)

The guitars I've been using so far are as follows: Tom Anderson Classic with Joe Barden pickups, 1974 Fender Strat with Anderson VA single coils and my Rickenbacher Bakelite lap steel. I ran the amp through three cabs. A 112 Mesa cab with a 25 watt Greenback. A 112 Rivera cab with a vinatge 30 and a very old Vox 212 cab with Vintage Celestions. I also ran it through the power amp section of my Rivera M100 head as well as a Fender Deluxe Reverb.

I play many styles, rock, country, funk, R&B, pop etc. This amp covers many bases. It would definately be a great studio amp. I'm not sure it would be loud enough on it's own to hang with a loud drummer but it works very well in a slave cofiguration. I found it to be very quiet even at extreme settings.
The Roll channel I liked best with the supplied tubes (EHEL34 and 12ax7's) This would be the channel to use if you want to play clean and use a pedal for solos and distortion. This channel will clip slightly if you max the volume but the distortion is very mild. What's great is how the amp feels. No matter how clean it's never stiff.
The Rock channel I liked best with a 6550 and a 12Au7 in the driver stage. There was still pleanty of gain on tap. This channel is "jump from the word go." Even with the gain at 9 o'clock you get a great sound. This amp works really well with single coils and is one of those amps that you don't have to turn full up to make it work. The tone of this channel really sings and is always smooth. Although this amp is very agressive (think plexi or tweed) it is never harsh. The death metal thing would not be it's thing. It's amazing how well the amp cleans up when you lower your guitars volume.

I like the way the tone controls work. Although just bass and treble the tone is easy to get right and the controls don't bleed like Fender tone circuits.

The amp sounded best through the 212 Vox cab. I have the THD cab on order. This is the cab I first heard it through and I know it sounds great.

I haven't had the amp long enough to rate the reliability. I brought it over a friends house. My friend is the tech that works on my amps and he also works for a company that builds guitar amps. He was impressed by the UniValve's sound and asked if he could look inside. He said THD did a great job inside and out. We really liked the quotes on the circuit board but I don't recommend a novice opening up an amp.

I've dealt with THD in the past and have owned the Hot Plate for several years as well as their yellow jackets. Andy fixed my 66 Fender Bassman head a few years ago and I've never had a problem with it. I'm sure they will stand behind their product.

I've been playing over 30 years and do so for a living. I've played clubs, weddings, in the studio and the last few years I've been playing Broadway shows in NYC and on the road. "Tommy," "RENT'" "FootLoose," "Aida'" and "The Full Monty."
My main stage amp is my Rivera M100. My other amps are my Fender Deluxe Reverb and Fender Bassman. I would definately replace it if it were lost or stolen.
I really love the feel of this amp. Because I've been playing show's for the past few years I'm usually stuck with whatever amp is at the theatre. It's a pleasure to go home and play a responsive amp.
I think the only thing missing for me would be reverb but I don't think it would be easy to put in this amp.

This is a really cool "boutique" amp that gives you the option of swapping your preamp and power tube(s). two inputs (not channel selectable),the volume adjusts the pre and power amp drive together, bass and treble, attitude (adjusts how hard you drive the power tube), simple noise reduction (works!),hot plate attenutor (lets the amp rock without blowing out your eardrums), and hi/low voltage switch. Its not a frills laden amp but very basic and straight forward with one goal in mind. THIS BABY DELIVERS TONE TO THE MAX!!!

I use PRS guitars, a fender strat copy, and a Brain May replica. This amp sings. the cleaner input (Roll)is sooo gorgeous. sparkling, breathy,and a nice break up depending on which tube you select. i generally don't like playing clean, but this amp is very sweet in that catagory. the Rock channel is another story. this amp sings!in stock form (EH 12ax7 and Svetlana el34)this sucker pumps out some serious grindage. thick, punchy, sustainy rythyms and single not runs. i was using a marshall avt 20 for practice. its up for sale. i heard this amp and fell in love with the sound and also the tube swapping option. i'm a NOS tube freak. if its current production, i don't want to hear it. i highly recommend the Yellow Jacket tube convertor especially made for this amp (YJUNI). it allows you to run an el84. OH my GOD, does that option SHRED!!! talk about Brian May on steriods!! with the volume and attitude pegged, you can slice trees with this bad boy. My next favorite power tube is a NOS Brimar 6V6, This is a classic smooth, tight, chimey sound. so thick and bell like. the el84 is a demon, whereas the 6v6 is totally angelic

don't know, haven't had it for that long. seems to be really well built though.

i've been e-mailing them (Ed DeGenaro)and he always gets back to me. he's suggested the yellow jacket, i ordered it from them (Carrie was very helpful) and got it in 2 days.

this is a great amp. not filled with bells and whistles and for the money, a WAY better buy than a modeling amp (i've owned several...i know). i have it running through a home-made cabinet loaded with a 10" Weber Blue Dog. Its a sweet combo. Take my advice don't buy a modeling toy, get the real thing. The amp tones, dynamics, etc change with each power tube you select. Not just the type, but even the manufacturer. I have 2 el34's that sound totally different. If you're a TONE FREAK, this amp is a must in your stable.

Current production Univalve amp head. Extreme versatility due to "voice morph" capability insofar as power tubes can be changed from one type to another creating distinct and separate sonic identities. These changes can be quickly done without having to bias the amplifier due to single power tube orientation. This easily qualifies the amp as diverse and capable in it's power class. No amp does everything so it stands to reason that this one truly holds it's own in an amp stable. Amp has other features making it even more adaptable such as the ability to create great "Marshallesque" "Plexi" tones at any volume given the choice between full volume output distortion and the built-in "Hotplate" attenuator. In addition, there is a line out section allowing direct recording and the usefullness of this amp as a preamp driving itself into the power section of a power amp or power amp section of a head set up to allow this type of operation.

I use this amp with every type of guitar. 99% of them are vinatge Les Pauls and Strats of various pedigree. THE PREVIOUS REVIEWER MAKES A FOOL OF HIMSELF STATING THAT THE AMPLIFIER DOES NOT HOLD UP AGAINST OTHER "BOUTIQUE" PRODUCTS SUCH AS THE BUDDA, BOGNER AND OTHERS. THIS USER IS OBVIOUSLY NOT VERY KEEN ON TONE AS ANYONE WITH A GOOD EAR KNOWS THAT PART OF THE UNIVALVE GREATNESS IS THAT IT CAN TAKE A SEAT NEXT TO THE CLASSIC DESIGNS..FENDER AND MARSHALL. AN EXPERIENCED EAR READILY REALIZES THAT BUDDA AND OTHERS LIKE IT DO NOT "CUT THE MUSTARD" NEXT TO A GREAT OLD MARSHALL "PLEXI" OR A CLASSIC TWEED FENDER OR "BLACKFACE" VARIANT. WHERE ARE YOUR EARS FELLOW? NOW, YOURS TRULY DID NOT MAKE ALL OF THIS UP. JUST GET INTO A ROOM WITH GOOD WORKING EXAMPLES OF THE CLASSICS LOADED WITH FINE VINTAGE TUBES. PLUG IN THE VINTAGE LES PAULS, STRATS, TELES AND WHATEVER ELSE SITS ON THE WALL AND......LISTEN. THEN, BRING IN THE SILLY "LET'S BE CUTE" BOUTIQUE AMPS WITH THE "RELIC" STRATS ALONG WITH THE GENERIC SOUNDING PAUL REED SMITH GUITARS AND...LISTEN. One is obviously superior to the other, if experienced ears adorn the listening room. Part of the trouble with today's "players" is they do not play well and they clearly have no knowledge of great tone and how it is generated. Hence, the radio serves as a living grave site from which the rotting "dead" emerge day after day tossing their dirt around the airwaves insisting the sound of the deaf and dead be alive after all. Nice try. The last review was just plain dumb. Still worse, it it "typical" of the "leadfinger" player of today. Oh, by the way, did I say you could make the Univalve sound like a terrific old Marshall at less than ear shattering volumes? Why, yes you can!

I trust it more than I would a Budda amp. :] <LOL>

A wonderful group. Seem to know quite a bit more about good sound than ethe people at Budda. ;-} <LOL>

It came to me complete. I never liked "boutique" amps until this one and the "other" THD head I've got. The THD "Plexi" chasis which has roared through my battered ears since 1995 without any trouble. Hail THD!