Ampeg SVP Pro Bass Preamp

I hooked this thing up with a BBE sonic maximizer and into a Mackie 1400i stereo amp, and was able to dial in some awesome bass tones.
I was playing through a Hartke 3500, which sounded good with the maximizer, but "boxy" without it. This Ampeg preamp blew it out of the water.
The manual is fairly basic. There's not much to know excpept to dial in your favorite tone. It's there!!

I can dial in any tone I want, as well as clean and distortion.
I don't use any stomp boxes, so I rely totally on my amps for my sound.
I play a Warwick Streamer Stage II 5 string inot this rig, and then into a Hartke VX115 and a Hartke VX410 on top. I am planning on purchasing an Ampeg 600 watt 410 cabinet, because I don't think the Hartke's can keep up with my rig.
The rig is virtually noise free when I'm not playing. I've heard people write about the noisy tubes, but I haven't heard it at all.

I've had it for a week, so I can't say how reliable it is yet, but I trust it wi9ll be fine. I always carry a back-up head to a gig, but I'll probably not have to pull it out.

I haven't had to call Ampeg, but have used the website to download information and manuals for Ampeg products. The website is easy to use.

I play modern rock and funk music, with a little classic rock mixed in. This rig has something for everything I play. I've been playing bass for 28 years, and guitar for 38. Besides my Warwick Streamer, I have a Schecter Studio 5, and a 1980 Ibanez Roadster fretless. I also have a Carvin C-850 acoustic guitar. My back-up bass rig is a Hartke 3500 amp head and a Behringer Ultra Bass 3000.
If this SVP-PRO were stolen or lost, I would replace it as soon as possible.
I wish it had a standby mode to keep the tubes cool during breaks.

I have a 72 J-Bass with active EMG's that is my funk machine. I have a 72 P-Bass with a 90's fretless neck that I use for some jazz stuff. I have a late 80's PRS 4-String that I use mor most electric stuff.

I use it for Jazz/Jam Rock/BLues/Funk/Reggae it is an all aroung great sounding head.

it can be very noisy if you do not match the tubes in it, play with various combinations of the AU7 tube till you find a quiet one.

Built in the mid 90's, they have a newer version now.
Very versital pre-amp.
5 tubes (1xAU7 & 4xAX-7's)

A built in Cross-over would be nice for bi-amp

see above, it is a tube amp so make sure you have them checked at least once a year and make sure you swap out the AU7 tube till you find one that makes it quiet.

I have called them only to find the order of the tubes and they are very helpful.

I love this pre-amp for electric stuff, I think for the weight of it compaired to a full tube head it is amazing.

I have been playing sice 1986 or so. I have tons of gear so I will stick with the bass stuff. I have a 76 Musicmaster bass (my first bass) that never gets played. I have a 72 J-Bass with active EMG's that is my funk machine. I have a 72 P-Bass with a 90's fretless neck that I use for some jazz stuff. I have a late 80's PRS 4-String that I use mor most electric stuff. I have a late 90's Knilling Upright with ebony fingerboard and a Davig Gage Pickup that I use for most everything.

Amps etc, I have used lots and lots of various combo's of pre-amps & pawer amps currently I am running an ampeg SVP-Pro > SWR 4004 for electric & Presonus Acoustic-Q > SWR 4004 for the upright. I keep a very old Music Man 120 Tube head around for backup.

Other reviews I have read have said that this unit is noisy. I find it to be absolutely quiet. The tone and depth and grind that it imparts is wonderful. It is easy to get TOO much love when you start to dig in. I am very impressed. It makes our little trio sound a whole lot bigger! I use this amp in conjuction with an SWR 750 X. I run my bass guitar lead into a channel switcher (actually a Loopmaster true by-pass effects loop). One output of the switchmaster goes to the SVP-Pro, which then goes into the effects input of the SWR. Another output of the Loopmaster goes into the regular input of the SWR (through the pre-map section). The SWR has an "effects blend" knob so that I can switch back and forth between the sterile sound of the SWR and the warm sound of the Ampeg. For bouncy, "Beatle" type sounds I use an Epiphone Allen Woody Rumblecat strung with flatwounds. It sounds great through the SWR pre-amp. For harder stuff, I use either a Pedulla Thunderbolt or Gibson SG Reissue through the SVP-Pro and I by-pass the SWR pre-amp altogether. I get the best of both worlds!

Made in 2005. See the Ampeg website for details. I play bass and and sing in a classic rock power trio and Ampeg is THE sound for the harder stuff. It has a nice array of features, although being able to control the amount of distortion remotely (switch or pedal) would be a welcome addition. It has a footswitchable EQ that I use as a volume boost during guitar solos.

I'm gonna give an N/A on this one. I just got it and hope that it is good for the long haul.

See above. I have not dealt with them.

This is a great unit. If it had some sort of remote distortion control, it would be a 10. It is pricey for sure, but it is actually less than the other pre-amps in it's class. If you crave THAT sound but don't want to carry around a huge all tube monster. Or, you're like me and you need 2 distinct sounds. This is the answer.

Fairly simple to use and eq to desired music styles. the slap eq was great.

very good when it was new

Can't depend on it solder joints on power supply broke down several times. This preamp stayed in the shop for repairs. Would cut out on gigs. It won't take the road beating. Maybe best used as a practice preamp for home use only. Will definately have a backup or an amp with it's own preamp section.

Don't have time between gigs to send it back to factory. It only was good thru the warranty period.

was a good match for jazz and R&B when new.

I've read the reviews, tried this unit out for a day, and I can't say I'm impressed at all!

While it is easy to use (if you can't set a graphic EQ and iput output levels, take up tuba), I had nothing but problems with this unit (see sound quality).

The unit right at the store had horrible buzz and microphonic tubes. After some serious grief from the sales guy (I've since been back and he was just having a bad day), got new tubes installed and checked it out.

I brought the unit home (with the assurance of a 30 day money back policy), and hooked it up to my SWR Stereo 800 power amp, SWR 4 x 10 and Cerwin Vega 1 x18 speakers. It buzzed like "mad hornets" as one previous poster said, and no remedy (tube placement, ground lifting, etc...) would rid the pre of this horrible buzzing.

Since I first tried the unit (microphonic tubes) and trying it at home (buzzing and noise), I wouldn't even try it on a gig where you are certain to have a higher noise floor (neon lights, etc...).

Gee, here's where I get a SERIOUS piss-off!

Ampeg's technician, after being explained the problem told me two things-

1. the tubes I was using "weren't good enough!" I needed low noise tubes for this. Now I've tried Teslas, Sovteks, EH's, even Old JAN GEs, and NONE of them "reduced" the noise.

2. I was also told that they couldn't help me with repairs (I do my own, having worked in the industry for over 15 years), as it wasn't bought from a "official" Ampeg dealer.

Well, Mr. Ampeg technician, if you are reading this- you've just cost your compnay a potential customer for life! If I can't repair something (even OUT of warrranty), on my own, or at least get some serious support, the company is NOT WORTH MY TIME OF DAY!

Wouldn't use it, and if it were stolen, the thief can HAVE the damn thing!!! His problem not mine!

I bought a Trace Elliot instead...

Getting a good sound is relatively easy, when it works.....
Manual is readily downloadable from www.ampeg.com

Might sound fine if the hornets moved out.
Buzzes like mad. Unacceptable for a piece of kit of this calibre.

No.
wouldn't gig it, it's going back in exchange for my money, thankyou.

Haven't had the chance. All I know is that the Ampeg site is quite useful.
Check it out before you buy one of these. The forum has a myriad of complaints about this unit humming/buzzing....

Try this with YOUR OWN GEAR before you buy one.
Mine sounded fine in the showroom, then turned into a dog when I hooked it up to my gear, which is equally good.
WHEN it works, it is capable of great results. Shame the reliability isn't there. What a waste of time and money. What a disappointment.
One bad experience has tarnished both my opinion of Ampeg products and of Valves forever. I don't expect perfection, but this is unacceptable.

This is an SVT in a one space rack package - preamp only, no power amp. Very easy to get any good sound from it. When you tweak the knobs the change is very musical and predictable. The tone controls and switches are tailored for bass guitar - you can get a world of tones from this preamp.

The beauty of the SVP Pro is that the tone controls are based around 12AX7 tubes, like the original SVT.

One really good feature is the MUTE button. This mutes the signal from all outputs except the TUNER output. You can use it to switch basses without messing with the volume settings and you can plug a tuner into the TUNER output so you can tune with no sound to the stage or the PA. The MUTE function is also available on the footswitch.

The graphic EQ is good - I plan on using it to EQ different rooms when I play out. The slidepots are real short but manageable with +8/-10dB of control - if they were +/-12dB or higher then they would have been too sensitive.

I got the manual from Ampeg's website and it is well written. It explains each knob/switch and the effect on your sound, and includes sample settings for different styles. The sample settings depend a lot on the bass guitar you are using of course.

The first you MUST do when you buy one of these is to replace the stock Sovtek/Chinese tubes with better ones. I chose a Groove Tubes 12AU7, while the four 12AX7s were replaced with Ruby 12AX7EHs. The immediate difference with the Ruby tubes is that they produced a hotter signal and they were much quieter. The Sovtek 12AX7 would really hiss when the TREBLE tone control was all the way up - not anymore with the Rubys. I swapped back and forth between the stock chinese 12AU7 and the Groove Tube and the GT had a better controllable overdrive. The overdrive from the chinese tube was too brittle, the GT is warmer.

I am using the SVP Pro as a front end bass processor for stage or for studio. When I am on stage I use a PA quality power amp to push a 2x15 cabinet. I tried a 6x10 cabinet but I liked the 2x15 better, especially for six string bass. In the studio I use only the SVP Pro and go direct to the console. That way all the tone comes from the preamp, no matter where I am. I also use a JBL/UREI 7110 compressor in the effects loop to even out the volume - I have the attack set slow so that the punches get through, which is a big part of the Ampeg sound.

The tone controls are three band with mid having five fixed positions for center frequencies (original SVT only had three position mids). The mid tone control is a bandpass filter and is very effective for fine-tuning your sound. The bass control has some serious thunder to it. The treble control is optimized for bass, something that a lot of preamps miss out on - I used to use a Tubeworks Blue Tube and its treble control was not optimized for bass, and with it all the way off that Blue Tube was STILL too bright. Also the Bluetube one has a single tube for its front end; the SVP has five total for front end, tone control, and overdrive.

The manual claims the EQ are active in that they are +/- 12dB but when you turn them all counterclockwise there is no sound - it acts like passive EQs on standard amps. However there is a nice big tube quality to the tone controls - especially on transients when popping/slapping or playing with a pick.

There are three EQ switches - Ultra Low, Bright, and Ultra Hi. Ultra Low does two things - it boosts +3dB at 40hz while it cuts -12dB at 500hz. I really like this setting. This is the AMPEG sound. The BRIGHT switch will boost +8dB at 2Khz - I don't use it all the time. The Ultra Hi switch will boost +7dB at 8Khz - this only seems to be effective when playing with a pick, because it highlights the sound of the pick on the strings.

The SVP Pro adds a DRIVE control that the SVT did not have. It is an overdrive circuit using a 12AU7, chosen for its lower gain. A 12AX7 is way too much gain; great for guitar but not bass. The 12AU7 doesn't distort as easy, the reason it is used for bass overdrive is because 1) it adds harmonics on loud transients while keeping a clean signal (think slapping/popping) and 2) the gain/bandwidth is controllable. In laymen's terms on the latter, when you push a tube too far into overdrive you can hear the bass response drop off, especially on those low B notes on 5/6 string basses. The hot 12AX7 would do this way too easily, hence the 12AU7. The DRIVE control works real good when your playing alternates between fingering and slapping.

Here's how I set up the GAIN and DRIVE: with DRIVE all the way off and 15dB PAD switch off, play fingerpicking style and set GAIN so that the clip LED lights only on peaks. If you have a really hot signal and the GAIN is less than 10 o'clock, then turn on the 15dB PAD and set the GAIN higher - the GAIN setting isn't very effective at low positions.

Then slap that mother while tweaking the DRIVE control. You loud pops will overdrive the 12AU7 which adds harmonics and makes that bass cut through. It also evens out the volume, because an overdriven tube has a natural compression effect. Tweak DRIVE to taste and remember if you go too far you will lose the bass freq

I bought this one used and it had some crackling in the sound. I took it to a repair tech and he found some solder joints that were cracked. When he fixed it the sound was much better.

I peeked inside and it looks well built.

I've been playing bass for over twenty years and have played in many styles - rock-n-roll, funk, soul, R&B. I grew up listening to Aerosmith and Lynyrd Skynyrd and have been broadening my repertoire into modern rock, funk, and classic R&B/soul. I worked with a Gibson RD Artist for a long time and as I recently expanded my musical tastes I bought a MIM Jazz Bass and later an Alvarez six string bass.

I heard some good amps, some bad. I heard Hartke amps and they are way too brittle, Peaveys are OK, SWRs sound wonderful, but the Ampeg SVT was king. I really liked that SVT tube sound, but the only thing that did not appeal to me was that massive head and its reputation of being sensitive to calibrate.

I wasn't aware of the SVP Pro until I stumbled across this one (used) in a store, and when I researched the web I decided that this was a good alternative to the classic SVT. I was right. The Ampeg SVT sound is all there, with a few extra bells and whistles thrown in to bring it up to today's world. Although the SVP Pro was not designed by the same company or people that designed the original SVT, it does get that SVT sound. The fact they used four 12AX7s for the tone control circuits shows how faithful it is to the original. Today's Ampeg is owned by St. Louis Music and many of their amps are designed by Lee Jackson of Metaltronix fame.

I had used a Tube Works Bluetube for a long time, but it only seemed good for one sound and it was too bright. The SVP has now taken its place although I reserve the full bandwidth of the Bluetube for vocals or acoustic guitar. The SVP sounds great and can get a wide variety of sounds. Now I'm happy.

Sounds quite good, just uninspiring to me. Reasonably flexible, but it seemed to me all the EQ options produced variations of the basic Ampeg sound, which isn't quite my cup of tea. Suitable for most music styles, warm clean to big mushy fuzztone. The drive control brings in a nice smooth overdrive, but overall the amp isn't very articulate.

Mid 90's Preamp. 3 band eq w/5 position mid frequency selector, 9 band graphic. 4 12AX7 tubes, 1 12AU7. Drive control, ultra lo and high boost switches, input pad switch, effects loop, tuner out, balanced and unbalanced outs.

Owned for about 10 years, no problems or tube changes.

Never had a problem, can't comment.

I liked the SVP, but it's voice wasn't quite mine. If you'd like to approximate the vintage Ampeg tone but want some flexibility, you would love it.

The sound of this tubepreamp is very ready without any hard eq-settings. For serious bottom its possible to use a 9band graphic eq and a ultralow switch, which cut the middle and boost the low end.
As a special feature this preamp does have a drive knob. The drive uses a 12AU7 tube. When not used the preamp sounds like an svt but turn it to 12 o'clock and its like a 70's Hiwatt-stack, but beefier.
The manual is simple, a block diagram,some settings and the usual front and back panel explanations. If the manual got lost its possible to download it from ampeg.com.

I'm using a Rickenbacker 4003s modified with badass2 and seymourduncan rickenbacker pickups. The other one is a 1983 Fender Precision '57 reissue(dakota red). I'm using this preamp through a crestaudio vs-900 poweramp. The poweramp is in bridge-mono mode(1100W) and it feed the ampeg 8*10" cab. I've owned recently a SVT-classic head. The reason I sold it was that I could get an even better sound through this setup, 20kg less weight,no expensive tube replacements, not have to worry about carrying it when its hot. Everything is nicely packed in a 6U rack-case. Just open the front/backpanels, give the D.I. to the house and go for it. A friend of mine said that don't buy any poweramp unless it read FOR BASS ONLY. So I contacted Ampeg themselves and asked if its possible to use this SVP-PRO with a poweramp. They said that any good professional poweramp should do the trick(+1000w). And they were right. The sound is now much faster, even dropped d-tuning was clear and very responsive, when you radically bend the string the amp will follow!. Many don't like transistor poweramp clipping, but with this setup which have more headroom than any "ready" amp on the market don't clip even after your ears bleed! This setup was a bargain. I got the poweramp for 700? and the preamp for 815? and a case for 200?.The footpedal is also nice, its possible to mute the whole system just by pressing the pedal and at the same time its possible to tune quiet. On gigs and in the rehersalroom its convenient to mute the amp and change instrument or effects and don't have to go to the amp and turn the master off. The settings stay the same. The other feature on the pedal is that it turns the 9 band eq on/off. I use it like a second channel. It is possible to shape, for example a deep dub-reggae sound with it.
I've been playing in bands for 15 years now. This is the first time i'm totally happy with my setup. I'm not going to this typical: I've used this and that blablabla. I've got a svt sound or an overdriven 100W Hiwatt stack with a touch of a knob. No worries about tubereplacements,carrying them or warming them up. Everything is packed safely in a rackcase.

A solid rackcase will protect the whole thing. No backup is needed

I've only sent some emails to them (ampeg). They responded quickly.

I play good rockandroll with some early heavymetal influences. The bass is very solid and cuts through two guitars if you so desire. The other reason why I sold the SVT-classic was that why do I carry a fragile, very heavy amp for just my own monitoring on stage. Because the sound to the audience is different. SVP-PRO has the same tubes as the Classic but driveknob is added. The preamp settings goes through D.I. to the board. Next time we have a recording session I'm only bringing this preamp and connect it to the mixer. I hope nobody will steal it from me, because I'm gonna install a gps-transmitter to it, you can run but you can't hide. Excellent job from Ampeg. Maybe some day I'll buy an old farty bassman and play some quiet blues but now I'm rocking with this for a long time.

One more thing: now I can put all my tube money to something else, Thailand, Mexico, 1966 Thunderbirdbass....

it's a preamp, it dosn't get much easier. some people may wonder what soem of the buttons do - you can find this out by pressing them. Sounds great flat which is always a good sign - this is pretty much how I use it. Don't have a manual or a reason to have one.

Excellent, it sounds like an ampeg. Some people may not like this though and I know what they mean, but you can't criticise it for that. I A/B tested it with the pod model and it is noticabley bigger sounding, Bass Pod is quite close though. It's quiet, I use it on top of an SWR Studio 220 which has a much wekaer sound (but more subtle) and an SWR Goliath Junior II cab. I play Sei bass (Flamboyant and an original), these basses have a pretty hot signal (ok the way mine is set up anyway) and the preamp can cope.

Ok I had a little problem with it once - there was a dry joint, but this can happen to anything so it really would be unreasonable to penalise it for this. As I bought it seconed hand I have no idea if the previous guy abused it....

Asked for the schematic - they mailed it to me quickly from the states to the UK. Can't argue with that!

I Love it, would definitely replace it. They're very cheap and I prefer them to most other valve preamps, especially over the single valve ones. Only wish they made the SVT Pro full valve amp this size but that would defy physics so I'll compromise.

The manual is entirely adequate, and comes in handy for defining the detailed functions of everything. You could literally plug & play though, as the control scheme is pretty intuitive. It's easy to get a good sound out of this pre right off the bat, and I think the unit has just the right amount of control without getting carried away. With 'different strokes' and all, a little knob twiddling will be in order for finding 'your' sound. Another area for consideration is the Drive and Gain controls, and how they work in conjunction with one another toward obtaining varying degrees of overdrive. Even with the Gain set as stipulated in the manual, adjusting the Drive knob affects the overall sound, and additional EQ teaks may be desired. Even still, this pre is not something that will drive you mad with knob twiddling and experimentation. Once the initial 'dial-in' trials are over, you're likely to find something you like, then stick with it. The only thing I thought the manual was lacking was a schematic for proper tube placement of the (4) 12AX7's and (1) 12AU7.

I'm running this preamp stereo into a QSC 1850HD. I have a BBE 482 in line via the SVP's f/x loop, but that's pretty much it. I run (2) 210XLT's off one side, and (1) 18" extension cab off the other. My main basses are a Cirrus 6 and NS4CR. I haven't used the graphic EQ on the SVP up to this point, but it's great to have should the room call for it. I've found the other controls entirely adequate so far.

Ok sound. This unit sounds great, and it really excels in a rock or blues setting. I play mostly hard rock, so I couldn't be happier with the sounds I'm able to get from this thing. I plan on using it for quite some time, and it hasn't left me wondering what I'm missing when considering other preamps. If you want a classic tube sound for rock, it's there, and with all the rich overtones you would expect. If you like things even more agressive, it's got that too. The Drive control, Gain control, and versatile EQ provide for a multitude of overdrive tones. The overdrive sounds are VERY well done too, always sounds good, never harsh really. The overall sound bias is definitely Ampeg, but then, that's something you know going in. Bottom line, if you play rock, hard rock, metal, or blues, check this one out.

The unit is also quiet, actually dead quiet in my rig. That is of course unless you get really radical with the high end EQ, but then, most equipment will hiss given that scenario. I haven't test driven the DI yet, so I cannot comment on sound quality or noise issues in that regard. The bass from the unit is not boomy either, but sounds very nice and deep even with the LOW knob at around 3 o'clock. Just don't go diming the LOW knob with the ULTRA LO depressed, or I'm sure your cabinets will let you know about it. I would prefer a more flexible mid control, but you can only cut/boost given the 5 mid frequencies they've selected. Still, the choices make some sense, and they are certainly usable toward getting a good sound. It's by no means necessary to get radical with the controls in order to get a ton of good sound here, and if you allow ample time for the intial 'dial-in' period, this unit will reward you with great sound.

So far, so good. I've had the unit for less than a year, but have had zero issues. I believe you get a 5 year warranty on these things if you buy new, so that's good piece of mind. Since we're dealing with only preamp tubes here, maintenance should be really minimal. I noticed a good deal of heat coming from the top vents after the unit has been operating at a stretch, but I have an empty rack space above the SVP in order to accomodate this circumstance. It would probably be fine regardless, but I figure it's to my advantage to alleviate any stresses on my equipment when possible.

Good rating, very responsive. I've emailed them several times in the past, and they usually hit me back that very same day. Never had to deal with them for warranty or repairs yet, but my impressions so far have been favorable. Plus, we're not talking about a start-up company here either, so the warranty really does help you rest easy.

I see this unit being mostly for rock, hard rock, and metal. There are possibly other genres that would benefit, but I'm a rock guy myself, so I'll leave it at that. For rock, definitely test drive one of these babies when you go shopping for a preamp. If it were stolen, I would probably go buy the same thing again (creature of habit). I like a lot of things about this unit, and my dislikes are pretty minor. I compared the SVP to other units, but based on a price/benefit type analysis, I found this unit to be a great value. The controls are effective, and never get in the way. With the kind of material I've been playing, I anticipate using this preamp for a long time to come. Like I said, I haven't even lusted after another pre since I picked this one up. It does the job for me day after day.

I usually use an Esh-Stinger 5 string with Kent Armstrong Pickups.
I also have a Rickenbacker and some other basses, but the Esh is my fave!
I play metal since...I guess 10 years and the SVP-Pro is perfect fpr that. You can have all kind of sounds, but NOT heavy distortion!! Something Ampeg should make better. Anyway..so I've used it with a Tech21NYC SansAmp Bass Driver DI to get more distortion. A Warwick WPA about 900 Watts (also stolen), an Ampeg 4x 10" and an Ampeg 1x15" helped me to get all out of it. The 15" kicked ass, the 4-10" was a good add-on but I've tried it with another 15"...had been better.

I've bought it 1998. It was stolen in spring 2001. Anyway..if I ever get enough money again, I'll buy it again.
9 Band-EQ, Distortion (could be better...too soft), Tuner-Out, XLR-Out - Pre/Post switchable, mute,..........

I had some problems when I've got the amp with the "In", because it peaked to easy. Changing the tubes is a lot of work because it's very hard to get to them. But after it has been repaired I used it without any backup every gig! So a clear...

never dealt...

Without the SVP-Pro I only have my old Peavy Mark3 Top (150Watts) but I've tried many stacks and pre's like G/K, TC Electronics, Hughes&Kettner, Trace Elliot, Marshall, Rocktron,...but no one of those amps could beat the Ampeg.

Start everyhting up the middle for a signature Ampeg sound (some extra emphasis on the mids). After playing a bit, activate the low and high boosts and hear the sound blossum. Why do they even need a graphic EQ? It's cake getting a great tone without it.

After the recent Groove Tube upgrade, the Sound quality is the warmest available anywhere. I know you're thinking Aguilar, Alembic, Demter . . . forget it. The Ampeg SVP has the standard in tube bass tone if that's what you're after.

Five tubes can be risky and I did have problems with the DI right after I bought it (which was remedied after shipping it back to Ampeg), but when it comes to the heat of the performance, forget it - The SVP will still be ready long after the roadies have clearded the gear.

Very friendly and reasonable. I got to know people there by name when they offered a tube upgrade and the warrenty repair was ungodly fast (wow! under 2 weeks!!).

I have played through them all for all styles of play and keep coming back to the SVP. It's not necessarily built like an Aguilar or as pro as a Demeter, but the peice just plain SOUNDS better - and why else are we into gear in the first place!

The Svp Pro is a very nice pre amp. It has a ton of very good sounds to go along with it's large number of controls that take a bit of using to master. I like the midrange control with it's five positions, I use position 2 most of the time, sometimes 3. The pre amp has an interesting control called "drive" that does alot to change the tone. You also have a "gain" and a master volume, so it is somewhat confusingly labeled. What it does is increase the drive to the preamp circuitry as well as smooth out the tone to make the overdrive sounds more pleasing. I use it sparingly sometimes, it's great to make an overly clean setup pick up some harmonic content, can really make it fuzzy and "Jack Brucy" if you want it to too. The regular EQ works nicely, just like it should, the bass and treble controls are centered at useful frequencys and the "brite" and "ultra high and Ultra Lo" are handy too. The manual is ok, it gives you a few ideas to try for some different sounds ranging from funk to country. The unit uses five preamp tubes and no solid state circuitry is in the signal path when you have the graphic EQ turned off. It's nice too by the way to add a finishing touch to the sound.

I use the SVP-Pro with a Carvin LB-90 bass,ART Dual Levelar compressor, Ampeg SVP-1500 amp and Ampeg 410 Pro cabinet. It sounds VERY impressive. It has power and punch because of the cabinet and amp, but the pre amp makes it have a nice pleasing sound that's a joy to play! I find it to not be terribly noisy and now that I've used the whole combination on several gigs I've got the sound nailed! I only use the effects loop to insert my compressor into the signal chain, the mute switch and tuner out are all nice features that work well too. Having a balanced out with a level control is great too, I send my signal right to the board through the snake with one mic cord, slick.

I did have some problems with the first unit right out of the box! A cold solder joint that I fixed rather than hassle with sending it back. I live in a rural area and sometimes this is the best thing to do. I had it going in about ten minutes and while I was working on it I got to check out the workman ship and construction which was quite nice. Don't let this scare you, I'm the only one I know about that's had this problem.

I ordered a manual for the SVP-1500 that I purchased used and they got it to me in a flash, no problem.

In our band we play lots of different styles, my Ampeg SVP-pro does this with style. It seems to sound great without hardly any fiddling at the gig. It does take a bit of effort to find your sound, but once you are familiar with the unit, it's great. Highly recommended. Do use a large amp and a cabinet that can handle it and it'll work great!

The SVP-Pro is a very versatile bass preamp, but a little tricky to get a particular sound out of at first. I assumed that being just knobs and stuff it would be easy, but there are a lot of knobs and they really interact with each other. The drive control in particular has a major effect on how the EQ sounds. Once you dial it in to your taste though, it sounds great, and the controls are very smooth and linear - you won't totally muck up your sound by turning a control pot just a little like some units. The throw/range of the controls is very smooth and musical.
No patches except the one you've dialed up. The EQ is footswitchable though, so you can set up a different sound with it.
The manual is very good, and gives some starting points for settings for different musical styles. The manual doesn't give you any info about replacing tubes though, instead stating there are no "user serviceable parts inside". I guess this is to keep Nimrods from electrocuting themselves (product liability CYA)- but hey, how hard can it be to change the tubes?
No firmware since it's not a software based product.
I also got the factory footswitch, so I could engage the mute without having to go back to the rack. It was kind of pricy ($29), but is pretty solid, has a classy Ampeg logo on it, and two LED's (Red and Green) on it for status. The footswitch engages the mute function and toggles the EQ in and out (two separate switches in one housing). If you're like me and like to get all the accesories with something, it's worth the money. One thing I really like about the footswitch is that it uses a standard stereo cable (TRS). These used to be hard to get, but are now readily available, in lengths up to 30'. With this type of design, if your cable gets roached, you can get another, instead of having to take the box apart and fit a new one, like with most footswitches that have the cable integrated with the box. Having a separate cable also lets you select an appropriate length, instead of the 5 or 10 feet they always seem to give you with a footswitch.
I upgraded the tubes on mine with RUBY STR 7025's (to replace the four 12AX7's) and a Phillips NOS Mil Spec Tube to replace the 12AU7. I did this to try and reduce some hiss (see below) - I would say it helped some (and improved the tone), but not really enough to justify the cost of the tubes. It would be a good upgrade after a number of years when the tubes needed replacing though

This thing kicks some serious butt. It has tone to die for - when I hooked it up I could have kicked myself for not having bought it sooner. I also tried an Alembic F1-X (which is a GREAT preamp), but the Ampeg won me over because it's tone has attitude with a capital A.
Especially if you are playing rock, roots, or any type of music requiring a cutting sound with edge and attitude, this is the one. It would also be good for more mellow styles (as I said it's very versatile).
I use the Ampeg SVP Pro for two basic setups. The large one, which I can rarely use live is biamped, with a Carvin 2 x 10 for highs, and two Carvin RL-115 (15") cabs for lows. I use a QSC 1400 (300 watts into each low end cab) for lows and a Carvin HT750 (one side @ 250 watts) into the Carvin 2 x 10. The output from the Ampeg goes into an Ashly 24 db/octave crossover (a refugee from my PA setup) to be split into lows and highs, and then the lows and highs each go into a separate channel of a Behringer Composer. The Composer compresses the highs and lows separately (a technique I heartily recommend, ESPECIALLY if you think a compressor kills your bass tone), and then feeds the lows and highs to separate amps and the different cabinets.
I had this stuff BEFORE I got the Ampeg, and when I installed it the sound of the rig became absolutely crushing. Before it was really loud and clean (I hate to admit it, but I was using a Peavey ProBass 1000 preamp) but had no real character. The first time I hooked up the Ampeg, the rest of my band was blown away - they thought my sound was great already, but this preamp really got their attention.
The second setup, which is what I mainly use out live is just the Ampeg into the Carvin HT750 amp, using one side (250 watts) into the 2 x 10 cab. Needless to say this does not compare to the big rig, but still really holds it's own. Sometimes I'll add one of the 15" cabs full range to this (using the other side of the amp), and this setup (500 watts into one 15" and two 10"s w/horn) sounds better than most rigs I've heard.
I guess the thing I like most about the Ampeg is that you can crank a lot of mids into your sound for definition of the notes without getting a nasal or honky quality to your tone. The highs are very glassy too, you just have to be careful about the hiss. The lows of course really kick too, and can make a small 2 x 10 cab (within it's excursion limits) sound really huge.
This preamp brings to mind two really distinct tones - the SVT tone on the old Van Halen stuff, and the Rush "Moving Pictures" tone. The SVP Pro really nails both of these, but can also excel at more contemporary tones.
My favorite "modern" sounds come from Eddie Jackson of Queensryche and John Myung of Dream Theater. The SVP Pro can do a good job of emulating these guy's tone as well.
The bottom line though is that this preamp can really give your sound it's own voice. Although it can sound like other stuff, it's really good to find your own sound. I think the fact that a guitar player, keyboardist, and drummer were immediately impressed says a lot. I've also gotten compliments from a lot of people when playing out with the SVP Pro.
As you can tell, I sort of like it.
Distortion - The drive control can be cranked all the way up, and in concert with the gain will give you that old "Jack Bruce" type sound. A little less will give you the "Moving Pictures" Rush type sound.
Not as over the top as a stomp box, but then again a lot more tasteful. If you record with this tone, you won't be asking yourself two years later "what the hell was I thinking" like you would if you used a stompbox.
I'm reducing the overall rating one point for the preamp hiss.
The only caveat is some high end hiss. This preamp is known for this problem, but you really only hear it if you are running a cab with a horn (4 x 10 w/horn or 2 x 10 w/horn). If you don't use a lot of treble boost, it's not too bad. I usually use a compressor with a gate (with my biamped setup) and

I have only had this unit for 6 months, but it does not seem to be a problem at all. I would gig without backup.
I opened it up to replace the tubes, and the inside looked pretty sturdy and neat. The tubes sockets WERE VERY TIGHT though, and the circuit board wiggled a bit as I pulled them out and put the new tubes in.
The only thing I don't care for is that the back panel jacks are the conductive plastic variety, mounted right on the circuit board instead of to the panel itself. As long as you keep the unit in a rack, and don't yank on the cables a lot it should be ok.

N/A - Although I've heard they are very good.
I haven't had any trouble so I don't know how good or bad they are.
Ampeg knows it's rep is based on it's Bass gear (yeah they do make guitar stuff too), so I imagine they try to keep people happy.
One nice thing is that there is no warranty card to fill out. Keep your receipt and the unit is warrantied for FIVE YEARS. That's pretty good in my opinion, in this day of 90 days labor, one year parts.

I play mainly rock, although I really like old and new prog rock (ELP, Dream Theater, etc.). I really liked the Alembic F1-X, but the Ampeg is the piece for rock (and cheaper to boot). Also the Alembic has that annoying DI on the front, and lacks modern amenenties like a tuner out jack.
I've been playing bass now for over 20 years, this is the best device for obtaining a great bass tone that I've ever bought. I started out with crap gear, then graduated to an Acoustic 220 head with two 1 x 15" JBL Loaded cabs which I used for about 12 years. Later I added the Peavey preamp and the QSC with two more cabs. Then I started biamping. I spent about 4 years changing cabs, adding amps, etc. and the Ampeg has made the biggest improvement in my sound. I'm totally happy with it (my sound) now.
If it was lost or stolen, I would have to get another one ASAP - I could't live without it.
I love virtually everything about it.
I hate the high end hiss, but I can live with it (for the record the Alembic F1-X was kind of hissy too, just not as bad).
A built in crossover would be nice, but since I use an outboard one it's not a big deal.
My favorite feature is the EQ. It's super flexible, and hard to screw up. It reminds me of a really good mixing console like you would find in a high end recording studio. You don't twist the EQ knobs to find a good sound, because it all sounds good. You twist the EQ knobs to find the sound that you want.
I compared it to the Alembic F1-X, which is a great piece. The Ampeg had more control, more features (except no crossover), and a better sound for rock. The price differential of $150 also played a part, but if the pricing had been reversed, I would have payed the extra for the Ampeg. (Note: I'm not dissing the Alembic, it's a GREAT Preamp, and in fact I think I will eventually pick one up).
Once you get your tone dialed in, it's smooth sailing with the Ampeg. the response to touch is really dynamic, and unlike my old preamp, I don't find myself continually turning up or down - get it set within the first song or two and leave it alone.
Again, I'm taking the overall rating down one notch for the high end hiss. If they fixed this, the Ampeg SVP Pro would be perfect.

This preamp is easy to use, once you familiarize yourself with the controls. The manual is decent, but it will take some experimenting to get your best tone. There are actually three controls to adjust your volume: gain, drive, and master. The ultra high and low, plus bright switch are great for someone like me, who uses a pick. I like a bright, trebly, but deep tone. The midrange is very versatile also, with two knobs to adjust the frequency voicing and range. The 9 band graphic EQ works in conjunction with the other knobs- something I did not discover for quite some time. Very cool. There is a pad switch for active basses. At the rear, there is tuner out, footswitch (for mute and graphic EQ),\ effects loop, twin preamp out, balanced out (with level and pre or post EQ).

I have two passive basses. One is a Fender Precision Plus ('91) ash body, maple neck, with Seymour Duncan Quarter Pounders (P & J), with a 2TEK bridge. The other is a Hamer Cruise 5, alder body, maple/rose- wood neck, Duncan Basslines jazz style, also with a 2TEK bridge. The Hamer is warm, bright, and has great tone, The Fender is very ballsy and punchy with the quarter pounders, with tons of output. I use an A-B box to switch quickly during live shows. My cabs are an Ampeg 410 Pro, and a 1x18 on the bottom. I feel the sound quality is awesome. I use the SVP with a Carvin FET 1000 power amp. This is the sound of rock, as far as I'm concerned. I set the gain at about 3/4, the drive just over 1/2, and adjust the master to taste (usually half way). You never need worry about cutting thru with an Ampeg, as the audience will not only hear you loud and clear, but will feel the bass in their chest.

I have had no problems, just be sure you use thick guage,like monster cable, speaker cords. It does make a difference with bass. I never use a backup.

I have not had to use the company yet, but I did email them once, and I actually got a response. Wow.

I play bass in a power trio, and my guitarist says Marshall and Ampeg go together very well. I love this preamp. Nothing rocks the casbah like an SVT. And this is that sound in a preamp. I will never need to look for a better bass sound, as this is it. My jones is satisfied!

This bass pre-amp , for the $, is one of the best I've played. True tube sound, controls are smooth, very linear. This is one of the only ALL-TUBE pre-amps out there for this money.Full control over bass, mids, treble, EQ, drive.

Delivers a warm sound (tubes), but you can get "solid state" influenced "piano wire" bass with the wide ranges available and roundwound strings. Since I use an SWR Goliath w/horn, I detect some approx. 1Khz preamp hiss (that you can't remove w/the EQ) even though I run the horn "way back". I plan "Hush" noise reduction for low volume applications and recording. Master volume only slightly increases hiss.

So far, no problems. Seems to run at a moderate temperature for an all-tube pre-amp. I would have no problem gigging w/o a back-up. Definately no special tribal dances or holding your mouth just right to make this thing crank.

No experience here yet. But the manual is very basic and sooner or later I will have to make contact w/them for specific information regarding electronic values not covered in the manual.

I looked at the Trace, SWR, Peavey, Ampeg SVP II (used), and hybrid or all-tube pre/power integrated units. I decided on the SVP PRO w/ Crown Power Base 1 (8 ohm bridge @ 430W) into the SWR Goliath (4x10 w/horn). If you want a very versatile unit for a variety of styles...this may be it. I like it!

It's not very hard to get a good usable bass tone from this bad boy. It's very controllable and flexible.

I haven't noticed any noise yet, what I have noticed is that this thing sounds killer! The tone from the five tubes is incredible, very warm and clean until you crank the gain or drive controls, and then it overdrives and distorts very musically and harmonically.

Very reliable and well built. All the knobs and jacks are very solid.

I would definetly buy this unti again. It has all the tone I expected and then some. Every bass player without a full SVT head and 8X10 cab on a budget should get one of these. Warning: This does alter other effect pedals sounds. My Morley Power Fuzz Wah sounds way better, and my DOD Death Metal sounds way worse. Also you need a stereo 1/4 plug to two mono 1/4 plug adapter to use the EQ and mute footswitch functions.