The JCM900slx is the best Marshall 👹👹

[ChuggNorris]

It's just how I feel.

It's so brutal and capable in the right hands. It hangs WITH a diezel herbert in the room. Which may be hard to believe... but it does.

The Sensativiy + Gain controls on the preamp plus the dual masters. Work so well together and cover early plexi tones all the way PAST hotrodded jcm800 tones with balls to spare. You can make it sound neutered like a current modded marshall or you can dial in some really thick usable bass. I lowered the bias a bit. They run HOT in stock trim. Benefit from being lowered in my opinion.

I've officially had this amp longer than any other amp with the Archon 100 being next after that.

Whats really funny is how so many used to hate on the amp and claim it had loose low end, not enough low end, not tight, blah blah.

These people simply didn't know what the fact they were talking about. It's so heavy and has just the right amount of squish under the fingers. Sounds incredible through Veteran 30's and Avatar/fane H75 speakers. Also greenbacks but I prefer the bass delivery of the others.

The right speakers and dialing, it stands so tall right up to a modern amp that cost 6 times as much.

Such an under - rated and badly used classic.

I've previously fixed the BR8 and recapped the entire thing (6 years ago) and it's been one of my main amps for years. It just hangs and hangs. Chuggy. Chunky. Heavy as a whaleshark.

 

[screamindemon]

Interesting, Always wanted to try one but never have. Might need to source one and try it out.

 

[ChuggNorris]

Interesting, Always wanted to try one but never have. Might need to source one and try it out.

Be aware, it CAN be dialed to sound like absolute shit. This is NOT a "all knobs at noon then tweak" amp.

The BR8 needs to be upgraded.

I recapped electrolytics etc with WIMA on the board and JJ filter caps. And added a blue LED.

Do not listen to people who say El34 version is better than 6l6/5881 version. I've heard them both and the 6l6 has more balls, and is more clear. The bigger difference would be if it's a 50 watt vs 100 in my opinion and the bias... I think guys played these amps with old tubes, failing BR8, and talked shit. Or then played one that was freshened up after and said one tube version was "better". It's just not true.

It's dead quiet at band volume unless you are being unruly with the gain controls.

It likes JJ preamp tubes and a 12at7 in the PI.
I keep a boost around just for kicks, because I never boost. It doesn't need one. But if you like it does take one very well.

It's thunderous and cuts at the same time.
It's not for everyone. It favors heavy handed picking and clean attack. And it cleans up nicely when you roll the volume on the guitar back.

It was a very misunderstood amp for a while. I think some have since seen the light. But it smashed my old DSL100. And it's stayed through ALOT of other high end amps.


You might hate it though

 

[glpg80]

They’re Marshall’s take on a 4 gain stage no diode clipping circuit. It’s basically the building block of many designs used today in its own right.

I’ve heard of them being put up against DSL100HRs tone wise. I played one and wasn’t thrown back by it. Pound for pound dollar for dollar I prefer a 5150 but that’s just MO.

 

[ChuggNorris]

They’re Marshall’s take on a 4 gain stage no diode clipping circuit. It’s basically the building block of many designs used today in its own right.

I’ve heard of them being put up against DSL100HRs tone wise. I played one and wasn’t thrown back by it. Pound for pound dollar for dollar I prefer a 5150 but that’s just MO.

Yes.... pure signal path single channel.
I've had every 5150 version and....
I prefer this to those hands down.

I think, possibly, if you were standing here in front of this one... getting pummeled... you might change your mind. I don't know how guys normally dial them or what configuration is ran but it can sound like ass for sure. I can make this thing sound terrible if I want

I still have yet to hear a good demo of one which to me is insane.... I really need to mess around with mics and recording to get the in room tones translated. Seems almost impossible but I've heard some do it.

Trying to tell people how good this amp sounds for thick heavy yet cutting rythem is like trying to explain what a good shroom trip is like to someone who's only had a bad experience.

When I say it hangs WITH a herbert... I mean it. Running it with the herber is the only time I use channel 3 on the herbert. Channel 2+ is like a darker version of the SLX, and without as much of the raunchy mids. I do plan to keep this amp forever regardless what else goes or comes.



Edit: this amp bends a dsl100hr over and takes it to pound town and I'm not even kidding. And I like the HR.

 

[NorCal_Val]

I’m not going to disagree.
I had an el-34/100w SLX.
It was the hot rodded Marshall I’d always wanted.
The coolest tone I ever got out of it, was Blackmore’s “Made In Japan” tone.
Holy crap. It sounded fantastic.
But, that was the SLX completely dimed, and the preamp and sensitivity rolled back.
Loud as f_ck.
I only sold it after I bought my Bogner Helios.
The SLX is one of the best Marshalls. Period.

 

[ChuggNorris]

I’m not going to disagree.
I had an el-34/100w SLX.
It was the hot rodded Marshall I’d always wanted.
The coolest tone I ever got out of it, was Blackmore’s “Made In Japan” tone.
Holy crap. It sounded fantastic.
But, that was the SLX completely dimed, and the preamp and sensitivity rolled back.
Loud as f_ck.
I only sold it after I bought my Bogner Helios.
The SLX is one of the best Marshalls. Period.

Hell yeah.....
One of many combinations!

The relationship between the master volumes and the preamp gains gives you ALOT of range and tone options. This is missed by probably 80% of people who have amps with these tone shaping tools. And for some reason they just won't try extreme or weird settings.

Marshall was showing the modders at the time that Marshall could do a better hotrod marshall than them and in my opinion it has stood the test of time. And with no switches... lol.

The more you try different combinations the more you learn how the actual amp wants to be operated. Often times, this is just too much brain work for especially modern players. Convenience is a big deal with these guys. They give up and say it sucks. Kills me. Happens all the time then amps that are killers get a bad rap. And for a while it was nice because these could be had for $600

I do want to get a helios though.
That's on the short list!!

I think I'd like it much more than the ultra for what I do.

 

[Smash]

Hell yeah.....
One of many combinations!

The relationship between the master volumes and the preamp gains gives you ALOT of range and tone options. This is missed by probably 80% of people who have amps with these tone shaping tools. And for some reason they just won't try extreme or weird settings.

Marshall was showing the modders at the time that Marshall could do a better hotrod marshall than them and in my opinion it has stood the test of time. And with no switches... lol.

The more you try different combinations the more you learn how the actual amp wants to be operated. Often times, this is just too much brain work for especially modern players. Convenience is a big deal with these guys. They give up and say it sucks. Kills me. Happens all the time then amps that are killers get a bad rap. And for a while it was nice because these could be had for $600

I do want to get a helios though.
That's on the short list!!

I think I'd like it much more than the ultra for what I do.

Not to shit on anyone's amp, but try a helios before buying. Next to the top amps, it is pretty vanilla imo

 

[ChuggNorris]

Not to shit on anyone's amp, but try a helios before buying. Next to the top amps, it is pretty vanilla imo

What did you feel it lacked?

And...
Have you played an XTC?

 

[Smash]

What did you feel it lacked?

And...
Have you played an XTC?

Shit. I have no idea now. @RedB4Black which did i play?

 

[RedB4Black]

Shit. I have no idea now. @RedB4Black which did i play?

Helios 50w

 

[VESmedic]

For what it’s worth, I bias all my amps on the colder side, always have. This is not just a phenomenon with the SL-X; anyone playing a high gain amp can definitely benefit from running a colder bias on their amps (unless it’s already super cold like the 5150) more bass, more low end, tighter, less shitty midrange, it’s a win win always.

 

[DanTravis62]

For what it’s worth, I bias all my amps on the colder side, always have. This is not just a phenomenon with the SL-X; anyone playing a high gain amp can definitely benefit from running a colder bias on their amps (unless it’s already super cold like the 5150) more bass, more low end, tighter, less shitty midrange, it’s a win win always.

This is 100% true

I think 900s sound quite good, but honestly I prefer a 2203 (especially a jmp) and a boost

And there are quite a few Marshall style amps I think are better - but maybe not for the price

I just sold a dual reverb for 900$ recently, and have owned two SLXs, and as far as bang for the buck they are underrated - especially the clean channel. They take pedals really well

 

[SoooRad]

The SLX is also my favourite Marshall. Sounds, great, dual masters were all the "technology" I needed. But, unlike the OP, I regularly ran it with all the knobs (including the master volume) at noon, and it was great sitting with a band. When playing at home I would turn knobs more, but in the midst of battle, everything straight up worked great.

 

[ChuggNorris]

For what it’s worth, I bias all my amps on the colder side, always have. This is not just a phenomenon with the SL-X; anyone playing a high gain amp can definitely benefit from running a colder bias on their amps (unless it’s already super cold like the 5150) more bass, more low end, tighter, less shitty midrange, it’s a win win always.

Absolutely! I don't know who started the "tubes hotter is better sound" thing. In my experience it loosens the lows and makes shit mushy.

I also bias colder. Like 50-55% of dissipation.

I think I'm running 6l6 at 30ma possibly less. Might be 28-29. It came from Diezel running something like 45 after it was on for a while.

I hate power tube breakup. As you play you can watch the Bias jump from 28 idle to 40ish on chunky riffing in real time. People don't realize if you have it up higher at 70% dissipation on idle, when you play it's hopping up into doodoo territory and forcing unpleasant power tube breakup.

It's one of the big misconceptions you see 75% of people still sniffing the cork on. "Hotter bias sounds better"

Definitely not! For what we do anyway

 

[JackBootedThug]

I have always wanted a 900… I used to be a big cathedral fan and dude used 900’s. Absolutely killer heavy tones on the first few albums.

 

[ChuggNorris]

The SLX is also my favourite Marshall. Sounds, great, dual masters were all the "technology" I needed. But, unlike the OP, I regularly ran it with all the knobs (including the master volume) at noon, and it was great sitting with a band. When playing at home I would turn knobs more, but in the midst of battle, everything straight up worked great.

Fugggggg yeahhhhh

That would be incredibly bright on mine.

I run mids on 9/10
Presence on zero.
Tiny bit of treble.

The mid knob is the tone knob on these amps. For me anyway.

It has mean cutting mids with a slight glassy attack on the top end without piercing harshness.....man I love it so much.

They really nailed it with this design. The lows fill the room when Im Chugging and it's a full package of tone that sounds great on its own while also sitting in a band mix very well.

It sounds and feels like tubes are supposed to sound and feel like. The amp is very much alive and raunchy. It barks back at me and gives me back what I put in. Very satisfying.

 

[VESmedic]

Absolutely! I don't know who started the "tubes hotter is better sound" thing. In my experience it loosens the lows and makes shit mushy.

I also bias colder. Like 50-55% of dissipation.

I think I'm running 6l6 at 30ma possibly less. Might be 28-29. It came from Diezel running something like 45 after it was on for a while.

I hate power tube breakup. As you play you can watch the Bias jump from 28 idle to 40ish on chunky riffing in real time. People don't realize if you have it up higher at 70% dissipation on idle, when you play it's hopping up into doodoo territory and forcing unpleasant power tube breakup.

It's one of the big misconceptions you see 75% of people still sniffing the cork on. "Hotter bias sounds better"

Definitely not! For what we do anyway

You know, I like you a lot….also that’s about what I run my Herbert at.

 

[glpg80]

Absolutely! I don't know who started the "tubes hotter is better sound" thing. In my experience it loosens the lows and makes shit mushy.

I also bias colder. Like 50-55% of dissipation.

I think I'm running 6l6 at 30ma possibly less. Might be 28-29. It came from Diezel running something like 45 after it was on for a while.

I hate power tube breakup. As you play you can watch the Bias jump from 28 idle to 40ish on chunky riffing in real time. People don't realize if you have it up higher at 70% dissipation on idle, when you play it's hopping up into doodoo territory and forcing unpleasant power tube breakup.

It's one of the big misconceptions you see 75% of people still sniffing the cork on. "Hotter bias sounds better"

Definitely not! For what we do anyway

Hotter bias gets away from crossover distortion. Percentage numbers mean nothing without knowledge of the plate voltage. The goal is not to be biased so hot you’re introducing third order harmonics in the power side but not so cold you’re biased hard class B and introducing crossover distortion in a class AB grid biased amplifier. There’s a sweet spot.

 

[Panhead5]

Typically I hate most of the 900’s but I had a SLX with 5881’s in it and it sounded great . Of course that meant I had to sell it.