JCM900 SL-X review by Marshall

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  • Sound: 9
  • Overall Impression: 8
  • Reliability & Durability: 8
  • Features: 7
  • Reviewer's score: 8 Superb
  • Users' score: 7.6 (14 votes)
Marshall: JCM900 SL-X

Sound — 9
I run this head thru differents guitars so they sound a little bit different, but being very sensitive lowering the volume knob on the guitar, giving the "clean" sound:

a) Washburn Slimebolt with 59' and dimebucker: plenty of power and thrashy sound, needs a OD for Th3 BrOoOtAlZzZ but the main feature of this amp is the DEFINITION, plenty in every stage of gain, very effective with the Dimebucker and warm with 59'. A real thrash machine

b) Fame the paul gothic with Alnico's II: arguably better than a Gibson les paul, the alnico's adds more classic bite to this amp. Great zeppellin tones and Hard rock, and surprisingly Great clean lowering the gain or the volume on the guitar.

Overall Impression — 8
Since I'm a Thrash player, this amp is a dream for me, clarity and power in one head, emphasizing the fact that this head was traded for my Spider valve. I match it with a Crate cab with celestions so the sound is pretty close to awsomeness for my style but this amp is not suitable for everyone due to the lack of channels and reverb, so investing in stompboxes is an option for the versatile player. Overall I'm very happy with it and recomend it for everyone Who wants aggresitivy and a responding amp for nuances of guitar playing, or combining it with a clean amp for more sound options

Reliability & Durability — 8
The amp was traded for my Spider valve 100 hd, and have annual revisions and valve changes, so it was cared. Marshall is very reliable so I'm confindent, they sent me the pedal for free (P801). It does not need back up if you care it but a clean amp can be useful for adding versatility

Features — 7
This little bastard, JCM900 SL-X version, was done somewhere between 990-1993. A hot rodded Marshall JCM800 with one channel with tipical EQ (bass middle and treble) and a presence knob, Master volume and a special gain knobs:

1 preamp volume 1-10
1 sensitivity knob that goes from 10 to 20!

Plus a channel A volume and Channel B what works as a volume boost with a P801 footswitch. It does have an ouput selector for 50w-100watts, effects loop,... Pretty simple but efective, lacks a really tweakable boost.

6 comments sorted by best / new / date

    I have been using a JCM900 combo for years for everything from folk and blues to metal and punk - it performs marvelously. You just have to set it up properly for what you are playing (and change the valves every few years like any valve amp). If you are playing at lower levels hit the power level mode switch on the back, that's what it's for. For blues and old rock and roll I just use the combo. When I am playing heavy music I sit the combo on top of my Marshall quad-box and run all 6 speakers, the combination works great. (Actually, all 6 speakers sounds pretty damn good for everything but you can get away with being lazy with anything short of metal)
    I own a JCM 900 dual reverb and its easily one of the best Marshalls I've played through. With a set of Mullard EL34s and armed with better speakers say...Vintage 30s or Classic Leads it truly is in a league of its own. I lucked out and got the first year model and surprisingly is very well rounded. I don't know what everyone is whining about the lack of bass for. Maybe they should be using a humbucker guitar through this amp instead of single coils ?
    I got a 50 watt JCM 900 with EL34's. It sounds fine. Some people just like to bitch...thinking it makes them sound like an expert or something. If you think it's too 'spiky' sounding (whatever that means) just turn down the freakin treble. Not bassy enough? Turn up the freakin bass. Too much gain? Turn down the preamp. Or you can act like an expert and just bitch bitch bitch.
    so im looking to get a decently priced marshall combo (valve) and reading some of the reviews on here been put off the jcm 900's I was thinking of getting, it is mainly for the cleans and il be using my board for the driven stuff so would this be ok?
    I have a heavily modded one in my room. They'll smash a DSL/TSL no competition however they're still crap. Too bright and thin, no balls, even with greenbacks (as the stock speakers is why they sound so bad) it lacks depth. Despite the JCM 900's lack of bass it actually sounds like a tube amp unlike the DSL/TSL I love the sound of it over most amps I've heard, if only it had the bass to compete.. A H&K switchblade would be a better option.
    for what i have read, the combo version and dual reverb sucks a lot in comparition with the SL-X...