Marshall JCM 900 4100 Dual Reverb

pretty versatile amp here 2 channels with separate gain master volume and reverb- and a half power switch-very nice- if it had dedicated tone controls for each it would be even better. Its big it's heavy but it's worth it for live gigs out of a 4X12 with 2 Relic 30's and two green backs it really moves a lot of air even at modest volume. All tube and one of the last breed of hand wired amps from the best thing to come out of Britain since the Fab Four!, oh and the Stones and the Who and Cream and Hendrix ( yeah it was England) And Zep etc...

This just sounds great! both channels are very cool- now i've been doing this for a long time and this amp gets way less respect than it deserves many die hard old school Marshall guys don't like it- period but if you take 5 minutes and play with the gain/volume of this you can pretty much geta very passable JMP sound or a JCM 800 sound- Clean channel will gget a very close JMP sound when pushed. I like not taking stop boxes- Best sound is pulling two tubes and running it on High power. a bit more claptonon bluebreaker sound. Doesn't have what my PTP wired JMP has as far as overall bark but where can you turn that up?

never busted

never needed

playing 45 yrs , not as versatile as my 6101 anniversary ( still think thats the best amp Marshall ever made!) but it sounded TONS better than a brand new 94 100 watt Plexi re-issue I had - as I said before at times sharing the tone stack could seriously affect performance but this one doesn't suffer as much as my early Boogies did from that affliction. Anything I wish it had- Someone to move it and the 4X12 cabinet

1996 version. 5881 power tubes. May as well have one channel, though it can be classified as having two.

Half power is useful; reverb is passable. Effects loop works well.

It fits my needs because it does many different styles without a lot of tweaking. However, since it includes the channel B that I never use, I'll rate it at a 6.

Sound quality is a 10. Easily.

I believe sound quality should reflect what an amp is capable of. My "trick" with this amp is to ignore the fact that it has a B channel and only use A. From there, it's crank the master - literally crank, not 7, not 8, crank - and then adjust the gain to taste. From there, I'd put this amp up against my $3500 Bogner 101b in a heartbeat. While it's not capable of everything the Bogner can do, if you set them up for the same type of the sound, they're just different; one isn't better than the other.

Specifically, I use it with a Strat and a Les Paul. I go from cleaner stuff, to lightly distorted blues, to rock and even metal. While it doesn't have as much gain as I could sometimes use, say for leads, what is does, it does with prowess.

Where does it not sound good? Channel B. It doesn't matter where the settings are, channel B doesn't sound good. Sonically, it's very thin with a lack of lows and not enough high highs to let the tone "breathe"; it's anemic. This is where the 4100 gets a bad rap, which is why they're so cheap!

All in all, it's a great sounding amp!

The previous owner for years didn't play the amp. In fact, when I got the amp, it had EL34s in it!! It was neglected; no doubt about that.

I threw some 6L6s in it, biased it up, and that was it. These are as solid as they come!

Have not heard great things, but I've never dealt with them.

Think and say what you want to, but I bought this thing after learning Korn used it on their first album! I learned it used 6L6s and that was about all the convincing I needed (had been wondering what a Marshall would be like with them).

The positives: what it can do, again, it does VERY well. Solid amp with a ton of power.

The negative: channel B is useless

Overall it is disappointing to see Marshall release an amp that has such great potential and yet falls so very short. It's like they took the JCM 800 circuitry for channel a, and used 6L6s since EL34s were made very poorly at the time. That much is awesome! Then, they needed to get more gain out of it, but got a little lazy, so they put DIODE CLIPPING in the gain channel! That sucks! I find myself sometimes wondering if they bothered to listen to it before it left the factory!

I'll give it an 8 because they're damn inexpensive for what they pack in channel A. I'd give it a 10, but since it's supposed to incorporate the second channel with more gain and it just sounds bad, its intended purpose isn't met.

1992 model made in England of course.This is the 2 channel independent reverb model switchable from 100/50 watts.Ample power to get the job done either way.Theres an effects loop and footswitch for channel switching and reverb I believe...mine is MIA!This model was supposed to be the "high gain" answer to the earlier 800's.Versatile? Well I can't think of anyone that gets a Marshall for it's versatility but as far as standard features it's enough.They were cool enough to put LED indicators for blown fuses.2 outputs (1 for each pair of tubes).There are 2 line out jacks in back.1 for direct and 1 for recording compensation.Not familiar enough with the workings of these to comment further.

This is where I'll need to split to a 2 part review.This amp carries a stigma of love/hate with it.Supposedly the worst amp Marshall ever made I've heard."Out of the box" I would tend to agree.The high gain is really a joke however the clean channel is fantastic.A nice touch over the single channel 800's.Reverb gets the job done.If you are looking for a pounding metal amp you WILL be disappointed BUT...KEEP READING...Don't give up on it.To wake up this AC/DC only amp you will need pedals.I got a Boss SD1 super overdrive and a GE7 Eq.Best investment ever.This thin,sustain starved and anorexic thing became a monster and wants to kill every other amp around now.The Eq alone thru the effects loop was 80% cure...seriously.This pedal has the volume control and 7 bands to mess with so you can get it all effectively using the volume to push the preamp.Depth?More than enough to be had.You will even be able to tame the harsh upper mids this amp is plagued with.Then add the SD1 and the sustain for leads WITH harmonics,all thru the dirty channel so as not to lose the Marshall tonal qualities.Bottom line is theres an awesome amp waiting to be unleashed so don't feel there's no hope for it based on other reviews.I like classic rock right through total brutality metal and with this setup you will get all of it.I've got a couple decent Jacksons,1 USA KV2 and an older Jap neck thru as well as a 95 Gibson Les Paul Classic custom shop all with SD pickups.Rating WITH pedals is 10 but for the stock amp a 5.

Every amp company has it's lemons and you also never know what will happen on any given day with a tube amp so no backup?Let's not kid ourselves.Mine was a used from ebay jobbie.It came with a blown fuse but promptly replaced it and have had no other issues yet but it's still kinda new to me so we'll see.

Heard the support from Marshall was kinda lacking but personally haven't needed them.No warrantee used.

Since these are going reasonably cheap used due to their reputation,I would say get one if you can.With the added volume control of the EQ it is no longer an amp that will only sound decent cranked but still does sound better that way.I hated the thing at first but have never sounded better since adding the pedals.This setup will keep up with amps selling for way more $ now and I'm glad I got one.I was considering the Line 6 Spider Valve head but no longer need to look further.My needs have been met and for less $ still.I've tinkered with the guitar since I was 15 and I'm 41.Bought and sold more gear than I care to remember always looking for something better.Since I don't have the bank account to get really high dollar stuff,settling for used has become the way to go for me.The JCM 900 4100 is a bargain given it's potential.Besides I've never met a Marshall that could do it all on it's own so here ya go.

Mine is the EL34 model, dual channel/reverb(gain and clean) with shared EQ(Low, Mid, High and Presence). It has both a Master volume and a pre-amp gain for each channel. Effects loop in the back with level control, Recording out(useless), 8 or 4(16) Ohm switch, high or low setting, basically runs the tubes in Triode when at low, also other stuff but im doing this from memory so I cants remember what else is back there.

Ok here is the part that has plauged these amps since their release. The problem with them is they use diode clipping in channel 2, now this for the tube purest its a no no, on the other hand they can get of their boutique amp high horse soap box and actually give this amp a shot. This amp is no easy fix to make it sing, I have had mine for almost 13 yrs now and it took some TLC to get it to sound the way i like it. Before I explain what I did to get it that way, Ill say what it sounded like before I modded/added stuff. The Clean channel was about the only reason I bought this, its warm and has just the right amount of overdrive if you want it to, also if you dial back on your guitars volume knob you can clean it up quite nice, then turn it up for some good ole' bluesy classic rock tones. The gain channel..well, it lacks, alot, fizzy gain, loss of low and jesus the damn high's will kill you! But i guess if you are doin some pop punk 3 power chord riffage you'll be right at home with it. The gain on channel two is basically useless after 3/4's, it really makes no difference if you stay there or go to 10(wish mine went to 11, but oh well). So yeah, the mod part, I kept asking myself should I bag this thing and free up the space, I never used this amp, I had my Mesa Dual recto and I was a happy camper for the time, but then i decided why not just mess with it until it either broke or I would use it. I spent quite a while on the net looking for an answer then i got my first step..http://web.aoct.org/marshall/jcm900-gain-mod.txt, follow this and you will not regret it! wow what a difference it made, suddenly I had this amp sounding like you would think a Marshall should! But i wasn't done, It still lacked, so I threw a Modded TS-9(pick a TS-9 mod, there has got to be 50 different ways to mod this pedal, all do ok stuff, mine is the JRC4558 op-amp with a few cap and resister changes, sounds great anyway look into it)BAM! again fantastic rich overdrive on either channel. Ok were almost there, so I started to use this amp now instead of my Mesa, I know crazy right, not really Im so sick of the "MESA is the only way to go" ********, besides I never once was told what a great sound I had with the mesa, and now everytime I fire up the JCM 900 people say what the hell! So i played with it for a while perfectly content with its sound, great gain, its good enough for any style you want, you just gotta know how to caress it. Then one day i bought the BBE Sonic Stomp, just because I figured it would sound good for my bass rig, I used it on my Marshall for fun(thru effects loop, very important)......MOTHER OF ALL THAT IS HOLY! It was just like they say, my amp sounded like a blanket had been lifted off the cab, beautiful tight lows, perfect mix of mid and highs all in a 2 knob box, seriously if you don't have one get it! Sure you can probably get a close enough sound with any EQ, but c'mon it has two knobs and workd amazing! Ok i know this isn't a review for the BBE so back to the amp. I know can palm mute this thing and it jiggles my belly, i can solo and blast right thru the mix(i play with a full band including the 2 other guitars, one Orange AD30 and the other uses a Mesa Triple) they both sound great but now its like a whole new ball game kids! Anywho, this has been wordy and kinda all over the place, but really just pick one of these up, I swears i see them all the time for like $250 on craigslist, its well worth it if you give it some love. Another thing with or without the mod, this amp loves pedals of any kind. Also the other thing is, its not a Plexi, Mesa Recto, Orange High gain, Peavey 5150, Soldano Hot Rod so quit trying to say it dosen't sound like one..it's not! YOu do however gotta crank this amp, just like most tube amps, its sounds pretty thin until you hit 12 noon on that master, but c'mon why not just got all the way!

Like i said mine has been in my hands since 1996'ish, and never had a problem with it.

Never had a need.

I use a 2x12 cab with Vin30's and a 4x12 with Gt12-75, Les Paul Deluxe and an American Tele. Pedals include the BBE Sonic Stomp, Ibanez TS-9(modded), Daddy-o overdrive(modded), Boss DD-3 delay, Holy Grail reverb, and a DIY volume pedal.

First run 1989-90 4100 with EL34s. Features are listed in prior reviews. I couldn't ask for any more features on this amp, other than no diodes in the gain channel and two EQs, one for each channel, otherwise everything you need. My output transformer has been replaced.

I use EL34s. I mention this, as there are two power amp tube versions of the 900. Also, people often switch to 6L6s or 6550's etc. I play a LP Standard with burstbucker pickups and a full pedalboard rig. I mainly use the clean channel with the pre cranked on half power mode and pretty flat EQ, switching to the gain channel only when I need a little more grit. I love the sound of the clean channel cranked, it's really the amp at it's best. It sounds outright flat below 12 o'clock on preamp or poweramp settings. Clean is not this amps forte, although it's not terrible. 100 watts is so overkill, the half power setting is the only way to go, through a 16 ohm cab. Tube breakup is necessary to remove some of the sterility of the gain channel. A pretty versatile amp all in all, and capable of solid tone, just turn it up. Reverb is decent and subtle, good for smoothing out clean tones.

I have been gigging with this amp for about 7 years, and the reverb has died on me twice. I had it repaired, and it died again. I don't mind much, because I use an EH Holy Grail into the preamp for some cool reverb through distortion splats. Also the stock output transformer blew in the middle of a gig once - worth noting. I had it replaced with an inexpensive upgrade, no Mercury Magnetics or anything, and it sounds even better. More note definition. All that aside, I feel like this amp is very dependable, and use it regularly with no backup.

Bought it used.

These amps go used for less money than most Marshalls, and they're a complete bargain. Not the king of the heap, but a solid gigging amp and an underrated performer. It's really become a part of my sound, and is slowly becoming harder and harder to replace, no matter how hard I try!

This amp has all of the features and functions that I use on an amp. In this sense it is the perfect amp for me. It has an effects loop with trim control, 50/100 watt switching, a lead channel, 3-band global eq, and my favorite: footswitchable spring reverb. REAL Spring reverb is often taken for granted. When you sort of "overload" the reverb chamber it gives off a haunting sound and sort of feeds back. I can't put into words what it sounds like. Some of you know exactly what I'm talking about. Just go to your local store and do it. Then you'll vever want another digital reverb pedal.

The clean channel is good, but not great. It doesn't have the thick, silky highs like a jtm or jmp marshall amp, but it does have that "glassy" sound. Especially with single coil neck pickups. Oh man do those sound great, especially with the reverb cranked. The Lead channel is beastly. I don't know what some of these metal guys are talking about. I have a les paul with a 498t bridge pickup and wow, I can get a good brown sound. It will get up there with the JCM 800's. It's a shade lighter. As far as clarity goes, the gain channel lacks the definition in your notes when you play a power chord or add notes to the chord you are playing. That's why I only use this channel for leads. I use a fulltone OCD on the clean channel for dirty tones when I'm not soloing.

if you've ever seen the pixies, my bloody valentine, or the lemonheads live, chances are you've seen/heard this amp. I've seen all three in the past 7 years and they had "killer tone, man".

I have dropped this thing a few times. I tour all the time, all over this great United States and I have never had a problem with this while I was on the road. Regular tube changes and I just got new springs in the reverb tank a month ago. My amp was built in 89 I think, two years after I was born. It's in better shape than me ;)

Never needed it, but I'm sure mr. Marshall has his hands full. I go to local guys anyways. Support local music and business.

Alot of people knock this amp because it doesn't have the bassier marshall tone that everyone loves. What people need to know is that Marshall was obviously trying something different with this amp. The highs on this amp are crazy sensitive. I keep the treble at about 2 o' clock at the most (on my plexi clone I keep it fully boosted for that tony iommi sound). I almost think this amp sounds like an AC30 on steroids. I'll tell you what, my plexi clone kills this amp a million times as far as tone and harmonics go. but That plexi doesn't have spring reverb and I wouldn't count on dropping my plexi and playing a show with it. This is the best live amp I've used. It is great for any style. Love it or hate, just don't knock it until you try it.

excellent example from Marshall but more versatile

Marshalls always sound scary at high volume,because of their power amp distortion. Very brutal and beautiful.

excellent quality workmanship

been playing for almost 20 years,owned a lot of amps. Marshall are the best amps

I love this amp when im playing live and you're there to feel its raw power, however on recordings it tends to lack its brute strength. I have used my JCM 900 on all of my bands recording with gibsons but always need to triple layer to get a heavy sound.

2 channels with reverb in each of them .Eq bass middle treble and pressence .Very usefull head.

Words from me are not enough to describe this head.The name marshall tells it all.The clean channel just crystal sound and the lead gain channel is maybe the best overdrive i ve ever heard in my life .The exellent eq that this head has it s very sensitive leting you make whatever sound you can imagine.THIS head is loud as hell.WORTH BYING IT IF U CAN FIND IT HAHAHA.

2 friends of mine plus me own this head and never had problem with something.If you are kind with this amp(make the nessesary service when needed ,change tubes etc)the amp will be kind to you as well.

1996 Marshall JCM900 100w valve head, model 4100.

4 x 5881 valves
3 x 12AX7 valves
Spring Reverb
Footswitchable Gain/Reverb
100/50 output switch

The JCM 900 is a simple split-channel amp, the clean and drive channels share the EQ section and only have independant gain and reverb controls. I only ever use this amp in the 50w mode, nobody should ever need 100watts unless you're ripping up a stadium. Its easy to use and doesnt over complicate anything. Would have been nice to have some sort of mid focus/contour control on the lead channel, just to give the voicing a wider sweep.

This is actually my 4th JCM900, but my first 100w version. The thing i love about them is the transparency of the sound, it sounds like a marshall always does but you can still hear your actual guitars tone, this is something that most modern amplifiers fall down on. The simplicity of the design means that the sound is very consistent in most situations, dont expect it to sound like a mesa or a 5150 because it never will, this is pure modern marshall. My main guitar is a heavily modded 50's re-issue Telecaster, bartilini humbucker at the bridge plus a high mass bridge and saddle set up. I also use an ibanez jet king jtk2 and an Aria Superstrat.

Clean - The clean on this amp is nice and choppy, its not overly deep or overbaring, which is great in a band situation, but you may need to add an addition EQ to the front end for recording just to make the tone jump a little more. Its a good sound for clean rock passages, ska punk or pop-rock, it doesnt really have the bite for fast country or the smoothness for soul and r&b. Push the gain on this channel and you can get some nice rootsy break-up, great for 70's rock and punk.

Drive - The drive channel is what i've always loved on these amps. The gain is nicely graduated until the last quarter and then it seems to lose its feel, i've heard this can be graduated further by changing the valve in position 1 to something a bit cleaner, but i like the sound of the EH 12ax7's i always use! The lower gain settings are great for subtle lead work and forceful rhythm chops, but the amp really comes into its own when you push the gain up to about2 o'clock. You'll be rewarded with a chunky, rich and musical distortion thats easy to control but sounds great. One thing you'll notice is the amps lack of mid range control, you'll frquently find yourself maxing out on the mid knob just to be heard above the drums, definately go for some EH tubes because they help project the mids and keep the low end tight.
The band i play in is a pop-punk/melodic rock band, its all original material, think jimmy eat world, spitalfield and yellowcard.

I've had four of them, aslong as they're serviced and revalved regularly then theyre reliable and road worthy.

Marshall doesnt even have any email details on its webpage!

I love jcm900's, they're very much MY sound. I never liked the 800's, DSL's we're good but very generic sounding, the new Vint/mods and JVM's are great amps but i still think that the 900 is the best modern amp they've built. Just make sure that you look after them well, in the next ten years this will become the marshall amp to own!

You can also pick these up mega cheap, especially the 5881 versions.