The JCM 900 was designed to be used at very high volume levels in order to get the amp cookin. At bedroom levels you’ll never get the desired results because the 900 was designed for the concert stage. Most reviewers base their reviews on bedroom volumes.

This amp was used on Silverchair's Frogstomp album, which had a pretty monstrous tone. Definitely an unfairly-maligned amp.

I used the JCM900 for my entire live touring career, always got compliments on my tone from fellow musicians. And yes, it needs to be stage volume to be at it's best. It's a great amp and channel A with gain all the way up is a GREAT distortion tone.

I think it sounded really good, to be honest. Don't really get the hate for these; it might sound 'thin' alone but that won't matter once you get a bass player in the mix. Saves you from having to trim your lows when that happens in the first place.

The only reason it sounds "thin" is because of the effect loop. "jump" the loop with a patch cable and adjust effect loop level to taste. If you search for JCM 900 Effect Loop hack, this is well documented.

I remember playing one of these in the 90s for a brief GAS chapter. Live in a power trio I was approached by a local golden-ear/good taste pro recording engineer gushing over how amazing my tone was. I think this amp reached a live audience much differently than it reached player's ears at home. Was SM57 in front of a G12-75, flat at the board. Incredible through the PA. I replaced it with a dual rec and was convinced it was "better" but those compliments dried up live...maybe shoulda kept it!

Are these the greatest amps Marshall ever made? No. Do they deserve their bad reputation? Hell no! These are decent. I only sold mine because GAS is perpetual. You made it sound dope!

I’ve had probably 100 amps over the years. It always amazes me, that guitar players think they can “buy” their sound. When in reality, most of it comes from your brain, your fingers, your heart and soul. Almost any amp can be tweaked to sound good if you know what you’re doing. I’ve owned many Marshall’s including 2 JCM 900 heads. I’ve found them to sound amazing, I would take one any day over a JCM 800, because of their versatility, which allows you to play all styles of music. I had an amazing guitar player friend years ago, who played through a old Peavey Standard solid state head. He sounded fantastic. If you find a good price on a JCM 900, buy it. Then practice and learn how to tweak it, so it sounds good out in the audience. Not where you are.

Great amp, very sturdy and well built like a tank. Got it brand new when it first came out, and still rocking. I love it.

I love my JCM 900 High Gain Dual Reverb 100 watt headand I am proud to have it in my fleet. It has an excellent clean channel and does everything from Soft Rock to Jazz to Country really well in channel one. In Channel two It also excells at low gain and high gain Hard Rock. Is it a modern metal amp like an EVH 100w Stealth? No but the JCM 900 was designed 30 years ago. It takes pedals well and it's extremely versitle and effective at many many different styles. It also sticks out in a mix with very little effort. One of the things I like about it best is that it has a unique voicing. It isnt like other amps.

I bought a new one in 92 and played the hell out of it for decades. Mostly because I couldn't afford anything else. I was always struggling with tone. Get it good enough, the next day come back and it wasn't right. Three things I did that was consistent and helped tremendously. 1. Music Man 4x12 bass cabinet. The bigger magnets made a big difference. 2. Mainly used the clean channel cranked. Added pedals when needed and rolled off volume for clean. 3. Effects loop never seemed to be that great BUT if I closed the loop with a basic patch cable and cranked the level it helped to tighten it up and upped the volume slightly. My version was 50 watt and it has a half watt switching the back. Keeping it at full wattage was noticeable.

One thing I will say, this amp might not be the funnest for chugging by yourself but it sure would blend into the mix with other instruments beautifully. It would just give the bass player more room to fill in the mix.

Not a huge fan of 900s myself but coming the 90s / early 2000 skate punk scene these guys can really capture that tone well. I could live with it if it was my only amp to choose from.

The JCM 900 rules. I don't think the mids of the 900 go particularly well with the V30's, for my tastes. I put Redbacks and Alnico creams in my matching 900 angled cab and it sounds killer. Also great clean channel on this amp.

The 900 with el34 tube is the sweetest best kept secret in history. The cleans have a light crunch and dirty channel is amazing. When I switched tubes from 6L6 to the 34s I ditched all my OD pedals. You will need a second amp for cleans though. A three channel version with a 6l6 side and a el34 side would be ideal

I own an early 80s JCM800 50W and a 2003 JCM2000 100W. Both have to be ridiculously loud to hear the amp sing as it was meant to. I added attenuators to both and now they both can be turned up without alerting the International Space Station. Huge difference in playability and tone.

A mate of mine played one through a 1960a with greenbacks in it and it sounded monstrous, totally astounded me I’ve never turned my nose up at one since

I loved this analysis of the JCM900! Excellent in-depth review. It goes to show that if you know your way around an amp/cab/speakers + boost, you can get a useable tone - not perfect - but usable out of most amps. I used to own a MESA Stiletto with frequencies that could cut through a lead wall...but when played through an orange 4x12...those harsh frequencies were eliminated and the amp rocked.

I subbed . Dude this is the best amp review I have ever watched . I thought you were a little hard on JCM 900 as the tones you got on first 2 pedals , lead channels or clean with gain cranked sounded beautiful. Low end is for bass player . But I respect your playing skills immensely. I dig your channel

So, my band played a show a few years ago. Band that played right before us was beginning their set, I’m side stage getting my stuff ready and I hear this guitar ring out, the most glorious, thick,chewy, heavy af but clear as a bell tone I’ve ever heard. Like, literally one of the best guitar tones ever. I went around to the front of the stage to see what he was playing. Jcm 900…. To this day it’s the best live tone I’d ever heard. Ever. I have no idea if his was modded or what. I chalk it up to Marshall being Marshall and accidentally making an amazing amp now and then.

I've been hoping they do a "Studio" version like the SJ/Plexi/JCM800, I have all 3 and this would be a nice addition.

Boost or OD in front, eq in the loop & there’s no stopping these amps. The 900’s can be a little stiff & unforgiving (compared to newer amps) and I guess this is where the problems may begin, for some. Great vid btw

My 4100 model with a Laney 4x12 loaded with Celestion M-70s handles the drop B, boosted, with EMGs just splendidly

4100 jcm 900 mods for modern sounds and high gain: piggyback a 10k resistor on R42 and change the treble bright cap c37 for a 270 pf. Don´t clipp out diodes, will oscillate sooner o later... stick a boss sd-1 at the front and an EQ pedal in the FX loop.... a real sleepper amp in the second hand market... with this mods, you will change your mind and never look back..... all your marshall tones in a solid built amp with as much gain as any recto or 5150..

I love my JCM 900 4500. It took me a bit to get it where I wanted, but once dialed in, I found myself going back to it time and time again.

I don’t know how popular these amps were for the metal scene but I know that they were used in the 90’s skate punk and pop punk scene a bunch. So I guess it comes down to what style of music you’re going for.

I think a lot of folks hated on these because of the G12T-75 speakers that the JCM900 cabs came loaded with. That and the: Oh NoEs ClIpPinG DIoDeS! As they put a boost in front of their amp. Personally, I thought they were good for the popular rock genres of that era.

Trey used dual JCM 900s with matching cabs in Morbid Angel. I believe there was cascading involved. If you blend it with another amp, the mix sounds killer. I kinda love the JCM 900 model on Axe Fx Ultra. I did own the actual amp for a couple years and enjoyed it while I had it.

I have the JCM900 SLX 100 watt. It sounds fantastic when rebiased hotter and has a fantastic master volume. I’ve heard people say it doesn’t use the same diode clipping a as most other JCM900s but haven’t verified this. All I know is I can get the Plexi sounds I like with a good MV and FX loop. There’s a lot of gain on tap but I mostly use it in lower gain ranges

I just sold my 4500, loved that amp. I've always preferred the 900s over *most* of the 800s I've played.

I've had the JCM900 50 Watt for years. Loved it in a live setting but found it a tad harsh when recording it direct. I did the Diode Clipping Mod recently...Wish I had done that sooner! Sounds really good...

These were punk band staple back in the mid 90's through early 00's. 2 channels and could be had at reasonable prices younger players could afford. My first band had one of these as our second tube amp (first was a 50 watt Hiwatt) and we loved it as we did some cleaner, ska-ish stuff. That said, in 98 our guitar player picked up a Rev F blackface Dual rectifier and it was a night and day difference; I remember comparing them and was amazed at how much more massive the Mesa sounded! That said, not deserving of the hate; lots of bands/players have made some good music on the lowly jcm 900.

I read an article with one of the guys at Hellspawn studios and apparently John Nodtveidt of Dissection used one these with a Boss DS-2 into a g12t75 cab for his main sound. He messed around with a Metal Zone but they say he preferred the Jcm900 with a DS-2.

I don’t know if I’ve only ever happened to play the “magic” ones but I’ve always loved the 900’s when I’ve jammed through them. It’s only been about 3 I’d say but they sounded phenomenal. But you did throw me a bit of a curve ball when I heard that opening part because that didn’t sound all that sweet to my ears haha.

IMO The three main issues with the dual reverb 900's are- #1, the fixed tone stack on channel B. #2 Channel A has 4 LED's as well. #3 There really isn't much gain from the preamp tubes. Some of the signal can bypass V1A. Most of the gain on both channels is from the OpAmps. One side of V2 is used to drive the effects loop. The other side is for reverb recovery. V3 is the phase inverter. I have owned a 4101 since 1995. I only use Channel A. It takes pedals really well. Or use the effects loop return so you just use the output section. It is pretty well built. It is made in England and the tube sockets bolt to the chassis unlike the JCM2000 which had the tube sockets soldered on the PCB's I really don't know what they were thinking when they designed it. The SLX is a great amp. I wish all 900's were like the SLX. I use KT77's in mine instead of EL34'S. This did give it a little more bass.

The trick is to make you get the EL34 model, not the 5881

4 minutes in I have the JCM 900 4100 U are using Celestion v30s. Mistake number 1.Tubes in mine EL34s. Use another speaker. I am using DV-77 . Sounds awesome too much low end!!!

I owned a 4500 and it was incredible! I think having 50w made the amp more “emulsified” with low end so to speak. Thanks for demoing this bad Larry.

I know it's an old video but just bought a JCM900 4500. WOW, if your Conservative with dialing in and an EQ in the FX loop, this amp comes alive with proper biasing and decent preamp tubes. Reminds me some of my 2205. I see why Trey from Morbid Angel plays through one. I also see why a lot of people don't care for them though. I really dig mine.

MV noon Put a patch cable in the FX loop, set that mini Loop pot to about 1130.

I wish I hadn't sold my JCM900 4100, I adored it and FOR ME it was the perfect Marshall. Absolutely adore the amp. Driving it with either Lace Sensors or a SB JB into a 2x12 with V30s and the tone was killer. And the clean channel is beautiful! To me the major reason so many people turn their noses up at it is because it's nOt AlL tUbE!!1! which means nothing in the grand scheme of things when this is basically the cousin of the Silver Jubilee and I don't see anyone telling Slash his tone sucked balls. It's also very harsh when people compare it to modern metal amps when that's not what it was created for - it's a hard rock/alternative/grunge amp and that's where it excels. Damnit it's making me want another one!

One of my favorite album tones was a Dual Rectifier and a JCM 900

This is outside the scope of this channel, but I work as local crew, and when Billy Idol, Pat Benatar, Joan Jett & The Black Hearts, and a few other 80's era bands and solo acts came through one of my local venues last summer, they were all using JCM 900 amps through Mode Four cabs or the stock cabs with Greenbacks and V30's swapped in, installed in an X/checker pattern array. Oddly, and very surprisingly, ZZ Top came through with amp sims, I wanna say it was Helix racks or something. Also, a JCM 800 with an OD pedal boosting in front and the gain anywhere at non-zero will sound very similar to a 900, though the 900 is going to be more low mids/high mids/high end heavy/ with true mids turned way down, leading it to be very scooped sounding.

Some of my favorite tones ever used 900’s

I was big into Rancid as a teenager. Ive wanted one ever since I saw Lars plug his Epi Les Paul into a JCM900 at the beginning of the Ruby Soho video.

They have this, sort of, hollow mushy grind to them that is just iconic for certain styles.

This amp isn’t bad but it has to be cranked as that is what it was designed for. I have to use my Marshall Powerbrake and crank the amp to get it to sound great at lower volumes.

Love the 900. Played an toured one with a boost via Keeley mod screamer for over a decade. Always tight never, in the way of the bass tone.

It needs to be loud, and I use a mesa style 5 band eq in the front, that does the trick

I picked up a JCM900 4100 some years ago....then went about finding the 1960a and b cabs to make a teenagers dream a Marshall STACK! .....I think using V30''s understandable because that is what you always use but the G12T-75's yield a different tone. V30''s great with a lot of amps but the G12T-75'S are voiced for this amp....world of difference? Maybe not but I know a lot of people that use their Mesa amps with Marshall cabs

I definitely don't think it's a bad amp. Not my favorite, but it most certainly can be pushed into something very useable. Like lots of marshalls, get the master volume up, bass and highs can be temperamental, don't skimp on the midrange. Overdrives help. It's kind of a great supporting amp, not a upfront, in your face amp. Great for rhythm guitarists and layering in the studio. Just my .02! Cheers

I ran a Mooer 005 EVH style preamp through the return w/reverb & delay through my JCM 900dr...it sounded pretty good.

A fun trick with these is to jumper the effects loop and there is a sweet spot in the loop level screw that fattens the amp up. Sounds strange I know but it absolutely works. Makes it much fatter and less sterile.

When I was 15 in 1991 I really wanted a JCM900 but I couldn't afford one. So I had to settle for a used amp the music store had, which cost me 200 bucks. It was a 1980 Marshall JMP Master Volume 2203 100w. That turned out to be a pretty good buy - I sold it a couple of years ago at a 500% profit!

The amp can get more low end with a power amp especially if it is a bass amp used as a power amp. You can boost the 120hz knob and it hits you right in the chest.

Sounds great for punkrock. I believe they use one in anti-flag, which I always liked a lot.

I play a Hiwatt DR 504 with an Orange PPC212 JCM 900 50w High Gain Dual Reverb Model 4502 combo. They are different rigs. I love them both. My JCM I only need my Morley bad horsie 2. Excellent compression, really has character. Tubes, cabs and speakers do effect sounds. If you can't dial a JCM in you need a Mesa Boogie Triple where it doesn't matter if you play single coils or humbuckers as no one can tell the difference. ENJOY.

I have owned this 212 combo amp from new as a first owner. I never abused this amp and always got the most decent tomes from this amp, especially using pedals to accentuate the sound and tones this amp can give. Yes, there are pros and cons to this amp but to be honest, there are pros and cons to any amp! If you know what you are doing and know how to handle what you have, then there is no question on how to make the sound you want/need. I bought this amp new and am the original owner of this amp. I use an EQ and sometimes a distortion pedal for additional boost. For me this Amp alone, with the EQ, can give me all I need to power a room more than what is needed unless you are playing an arena and at that point you would be going direct output to the board to whatever affects you want to use. I personally have a very positive review for this amp and love it. I know it uses Diodes for the overdrive, but the sound is very good and not poor at all. It is Marshall quality. I also use this amp through a Laney 410 guitar 240 watt guitar cabinet which makes a HUGE difference in the sound. The Laney uses Fane speakers which add tp the great sound as the 410's are tight and can bring a lot of bottom end. The bottom line on this amp is how you use it and what you use with it. Alone, the amp is bare and needs help but once you add an EQ and a 410 bottom cabinet, changes the entire game and sound of everything. The amp is GREAT and i would not change it out for anything except for my ''67 Fender 410 Black Face Super Reverb 40 watt If you are going for Metal the Marshall is he way to go but if you are going for Blues, the Fender cannot be beat ever!!!

Like you said, you can get amazing tones out of the 900 with the right cabinet, the right humbucker and the right overdrive pedal. I use a peavey XXL through a Randall 4x12. I don't need any overdrive pedals because there's so much gain and saturation in the amp itself. The peavey classic 60 tweed amp is perfect for classic rock tones.

Damn, the sound around 12:45 is almost that Alpha & Omega studio 1988 thrash sound that records as Forbidden Evil (Forbidden) and Eternal Nightmare (Vio-Lence) have. Great thrash metal sound.

You definitely need to experiment with different cabs and Speakers to get the best out of the 900s. H magnet speakers work really well like a Celestion Red back . Another Great speaker for the 900 is an early 80s G12H80 55hz or a mid 80s G12H100 55Hz . The Creamback M65 sounds nice as well with the 900.

Totally agree with barano and Jeffeffect, high gain channel B volume needs to be around 7 on the dial before you can really get those tubes going. As shown in the video, using channel A to roll off the volume gets you a clean sound. turn the git volume up for the classic rock rhythm tone and then stomp the footswitch to channel B for leads or metal. All with the volume knob at 7 or above on the amp. (not 7 o'clock) It's a great amp! More practical to gig with than my Triple Rec.

Been waiting for this one. You upload on my birthday. Thanks 🙏

From my experience, the 900's lack of low end (boosted with SD1) let the bass shine brighter in the mix... jmho

Am I the only one whose noticing Kyle's microphone audio popping and crackling? I've noticed this in many of his videos.

I'd really like to see some content featuring 50-100W combo amps...there are a lot of combo versions of amps like the Rectifier, JCM800/900, and 5150 that are awesome and don't get enough love! Not everyone has the room or need for a 4x12, no matter how awesome they are lol

i have a jcm900 and did a few modifications on the preamp. Its now one of the best sounding amps ive ever played and recorded with.

I had one but sold it because you have to play it loud. People think it’s thin sounding, but in a band mix it sounds great.

I played a 900 Mkiii for years in a punk band. They sound best w KT88 tubes and I prefer a TS drive pedal. I got tons of compliments with it and it was never in the shop except for tubes. In the end, I went to Mesa Mkiv and never looked back.

Served me well for 15 years - you just got to learn how to use an amp - only retired because it’s SO BLYDI LOUD AND HEAVY. Downsized in the end. But every now and then when the house is empty I crank her up. It’s like the word of God. Rattles the ribs I can tell you.

I remember buying one of these in the mid 90'ss. I returned it the next day. Hated it!

i love my JCM 900 50 Watt....The 50 Watt..has the advantage that the power amp kicks in earlier than its big brother with 100 watts. It rocks really well

From what I remember, even the 2 other 900s had a much darker tone. In YT 900 shootouts, the Dual Reverb sounded thin as hell.

I had one in the late 80s. Great for classic rock.

The guitar player for Tower of Power played through a JMC 900 I know I talked to him on stage and I was digging the sound I said man your amp sounds awesome oh wow it's a JMC 900 when they first came out

I have the 50w version loaded with 6L6 (came that way when I bought it), the volume has to be cranked to get a better tone which I know you already know that. I made a "attenuator" pedal so I can crank the volume to about 2 o'clock set the gain at 1 o'clock and then add my Friedman Buxom Boost or Mosky Silver Horse and bingo 👌

I modified my jcm900 so the plastic logo now says "Mallrash" and it sounds way better. Tone is in the logo.

Sounds good with the sd1, amazing what a $50 dollar pedal can do

I've always felt like EMGs (espicially the classic 81/85) and Marshalls go together like pepperoni on pizza. If I'm playing metal, I don't want one without the other, but together they're my favourite. One thing I think all Marshalls have in common is that they're a lot more "transparent" with your tone than other high gain amps. They care a lot more about the type, hotness, and height of your pickups, how you have your pedals set, etc, whereas a lot of other amps will just put a nice comfortable layer of overdrive over the top of your fundamental tone.

This amp is the sound of skate punk to me. Great in a mix

I'm yet to grab one! So many great metal albums have been recorded with a JCM 900. It's Trey Azagtoth main amp to this very day ✌️

Sounds great. The JCM2000s got pretty panned at the time too. I get the feeling people just don't like these because they don't sound like the old Marshalls. Even the 800s had a bit of the old Marshall vibe.

I wonder how many people complaining about diode clipping are also running OD pedals?? Personally, I've had one since new, still love it. Not a super hi gain guy though and I run pre amps into the power amp

I've always been interested in the JCM from Marshall. Thanks for the heads up on what to expect! Also I love the Balaguer guitar!!

Do you own, can borrow, or have tried, the TC Electronic Mojo Mojo overdrive or Dark Matter distortion? In my humble opinion they both have a lot of low end and may work well with this JCM900. Just guessing. Maybe you can do the test. Cheers bro. As always, awesome video.

Sounds like a good pedal platform amp for classic rock. And you can have it modded to make it less bright. You certainly can do Joe Satriani type stuff!

JCM2000 DSL100MLB. They made a tiny circuit change in the MLB heads, and they blew up CONSTANTLY.

I got a lot of compliments on my jcm 900's tone live. Some guys had 1000's in their setup while I just had maybe a $600 setup.

Oh, I forgot to mention that in the 90s we always dialed an amp in like this: preamp:10 master:1-3 Bass:10 Mid: 0-5 Treble; 3-5 Presence: 2-3 Reverb: 0-5 !!

Ahh, my main amp for years because I was a Trey Azagthoth fanboy, except mine was the SLX version (apparently the "good" model). The frustrations you're describing were my exact issues too, I had the 16K fader on my MXR 10-band nearly all the way cut for the same reasons.

I have a 1990 MK III 2100 single channel full stack. Great amp and made to turn up loud especially with two cabinets. Put some nice tubes in the head, mix of newer and NOS and it rocks. Agree with other comments, these are not a low volume bedroom amp.

I’ve played two different 900’s and both lacked that extra step. They need lots of help to sound good.

I have a jcm900 cab I got for dirt cheap and I've always been curious about the heads themselves but it seems I can only ever find these and not the more sought after ones like the SLX at least not for reasonable price. These amps sound evil when you dial them right as you've demonstrated. I've been on the hunt for a decent budget marshall style head that can hang in a band and these might actually have a chance now that I've heard you play it.

Sounds great through my ox box and torpedo captor x I have 800s 2203, 2205, dsl40cr, jvm410 I can dial in similar tones on each of my amps If you lower the distortion on the 900 and add the same stomps most of us use anyway You will be using the diode in the stomp (if you don’t like the 900 demon diode) and the power amp breakup I don’t own a Marshall I can’t make sound good and I have used every amp in my life as a stage and studio musician What’s funny is if the price was tripled you would not be able to find one and if one respected guitarist Started using the 900 then the perceived value goes through the roof We played plexis because that’s what we had and then for me the 800s came next It’s an interesting exercise in marketing and psychology Sounds great to me I use this amp with a 6 band mxr eq and all is lovely

I love mine I run a mxr od 10 band e q with a frowny face and my mids low and hi at 1 o’clock plenty of gain usually play at a 3 on volume.

This thing will actually start to get some pretty good low end thump going on, but the master needs to be at 1 o’clock. I just found this out messing around with it in my garage today. Below that it doesn’t have much even with the bass dimed. And obviously having it at 1 o’clock is loud as shit. I also tend to run the presence and treble low, it’s a bright amp. This amp pairs really well with my evh 4x12 with the g12evh celestions. I’m not sure v30s are the best match for these amps as the grindy upper mid is something the amp already has a lot of and the v30 accentuates that.

I have the jcm900 4101 combo which I rebuilt the chassis and made it into a top with red tolex..

As someone stated in the comments already patch cable or something in the loop helps a lot. I’ve had one with 5881’s then converted to el34’s. Loved the warm clean but still missing low end for me. Ended up getting a 2203 reissue and modded it with a depth control. Love it. Still do kinda miss the 900 tho I don’t think it deserves the hate. I think people give up rather quickly in favor for something in comparison like a 2203. Although the clean channel seems 800ish with a different voicing. When changing channels you can hear the ummp loss 😕

On a serious note I really like the heavy crunch settings you pulled out of the amp. I could see myself using that with my band and getting by just fine.

Great video! Have you done a demo of the Marshall Mode Four? That would be fun to watch!