Old JCM800s

[ErikH]

Re: Old JCM800s

Thanks ErikH!~

You know what sucks about having those amps? Trying to decide which one to play!

I bet. You could always run your guitar in to a stereo chorus and then split it out to both amps. Now that would sound sweet.

I'm pretty content with my JCM900 MkIII 100 watter. My amp tech gave it high marks when I asked him about it and I love that the tube sockets are hardwired, not PCB mounted.

[B2D]

Re: Old JCM800s

Reading this thread and sucking up all the info...

Hey Jeff! I have an idea for those new amps of yours after reading that 2nd reply of yours...

In a 100w amp, Is there any possible way to add a function that will drop the amp to 25 watts instead of 50?

[JeffB]

Re: Old JCM800s

I like the 2210 or the 2205 best, it is a Michael Schenker thing

Which era in his career? He didn't start using the channel switchers til the late 80's. Personally, I feel that is when his tone went downhill (it's also the same time period he gave up wahs cos he couldn't find any "good" vintage ones anymore).

UFO days were NMV's (1987)... for the classic MSG days (The Michael Schenker Group album through Rock Will never Die, the live album) and some of the first McCauley Schenker Group album, he used stock and Rivera modded Marshalls (1987's mostly).

If you can find the BBC radio One live CD from UFO, check it out, and compare Rock Bottom (or hell the studio version off Phenomenon) to something like the version off The Unforgiven Live album or whatever it is. Quite a difference.

But I'm getting Wayyyy OT here

[The Golden Boy]

Re: Old JCM800s

The tone difference I hear is (w/ 6550s)..a shift in the high frequency, and more compression I would say. They don't sound as "gritty" or "crunchy" and lose some high mids & presence. Tighter. Rounder. It's not necc a *bad* sound Dave, it's just different, and not my preference

Describing tone is such a pain in the ass

I hear that high frequency "shift" you're referring to. Funny thing is, I only recently started attributing that to 6550's instead of a charcteristic of individual amps. I'll disagree with you about being more compressed, though. I find that amp to let more of the different guitars' individual characters to show through, even through the higher levels of gain. Where you're saying they're not as "gritty" or "crunchy," I say its more smooth.

The sound of that amp has always been remarkably consistent with my amp, and what's interesting is that I have as similar sound as I figure I'm going to get out of the Park by swapping out the pre-amp tubes for some Mullards. I replaced the Sovtek set in the Marshall and that didn't make a bit of difference, but it was night and day in the Park. I've never been much of one to do a lot of hunting down tubes- If I walk into them, cool, and I'm happy when I do, but that was an interesting change.

[The Golden Boy]

Re: Old JCM800s

I really enjoy waiting 7 minutes to find the server timed out and hitting the refresh button to come up with a double post. I apologize.

[WhoFan]

Re: Old JCM800s

TONE- Thanks for posting that JCM 800 article...... first thing a tech i know asked me when i told him i had bought an 800 was if the imput jacks were Horizontal of Verticle..... He was happy to hear mine were Vertical

WhoFan

[man-in-moon]

Re: Old JCM800s

i voted for the 2204 i had one awhile back and loved it.

[pinto79]

Re: Old JCM800s

I have owned 4 JCM800 2204's, 1 JCM800 2203, and 1 JMP 2204. I liked the JMP and one particular 800, one that had been owned by Bob Rock. All of mine were the Vertical jack MV's and the Bob Rock one had THE tone. I re-tubed it with GT 7025's and E34Ls's Matched at #7 and with a "mere" 50 watts and a worn-out Sunn 4x12, was able to completely drown out a 400 watt bass stack, a Drum Set and the second guitarist cascading 2 100 watt combos.

I never should have loaned out the Rock head which was convieniently "stolen" from the borower's practice space... fortunately I had one of his 800's as collateral, which I sold for more than I paid for mine, but it's the principle...

I found one other one that came close to the Rock, but I ddn't have the $$$ at the time.

I tried a re-issue that was a dead-ringer for it also.

I can still hear the tone...

The 800 takes pedals like nothing else. And my best sounding ones all had Drake Trannys. Drake Rules...

BTW, I voted 2204....

[Robert S.]

Re: Old JCM800s

When I converted my 2203 to EL34s the tone did get more mid present and the distortion smoothed out quite a bit. I wouldn't call the tone of the 6550s grainy but it was a little rougher around the edges. The 6550s definately had more headroom and were brighter to my ears.

I prefer the EL34s in my '84.

[krankguitarist]

Re: Old JCM800s

the continuation of the article:

Unfortunately these new 2203's just didn’t have the same “punch” or power levels. Sure, they were still loud, but were much more grainy and thin-sounding as they were turned up. It did NOT help that at around the same time, the U.S.A. versions of the JCM 800 series began to re-adopt the EL34 tubes, which otherwise could've been a blessing. For Marshall’s best-selling 2203 and 2204 single-channel master volume heads, the switch in tubes actually limited the tone further since the 6550 – while not as quick to break up – still provided a fuller tonal range in this particular configuration. In essence, the "three-capped" 100 watt JCM 800 was the first Marshall that did NOT necessarily sound better as the volume went up - in fact, it began to sound worse - more grainy, thin, and muddy as the volume increased. REMEMBER: THIS is simply MY opinion represented above - you may prefer the later JCM 800's as is your right to do so!

there is alot more on Marshalls on the site!

I can vouch for the whole "horizontal vs. vertical" input thing.

I used to have a horizontal JCM800 2203, and it was real grainy, a real thin sounding amp. It was one of the last production years that the original JCM800 was made.

Now, a while back I was in a band with a guy who had a 2204 vertical input model. I had the oppertunity to play and work on that amp a bit (as well as compare it to my old 800), and it sounded considerably better than my old JCM800 did. Lots of crunch, lots of power, lots of presence. Made me kind of jealous .

I'd say go with a 2204, cause there really isn't much volume difference between the two, and those things can seriously rock.

[B2D]

Re: Old JCM800s

*bump for Jeff to answer my 25-watt power function Q*

[keano12]

Re: Old JCM800s

Ok i don't get this vertical horizontal thing? Are you talking about the amp input jack?"

Also I heard 6550 give an amp bit more low end and tame the hi mids. Sounds good to me?

[Lake Placid Blues]

Re: Old JCM800s

Yes, the input jacks. The vertical inputs have the pots bolted directly to the front panal and they are wied up with flying leads. In the horizontal versions, the pots are attached to the PCB and the shafts just go through the holes on the front panal, holding both the pots and the PCB in place. It was much less expensive, and much easier for semi skilled labors to assemble the amps.


The thing about 6550's, is that it's much more difficult to get them to breakup at reasonable volume level. The classic Marshall sound is based on output stage overdive. If you don't want ouput stage breakup at lower volumes, then 6550's are problaby fuller sounding than EL34's, when properly biased.

I'm not Jeff, but one way to reduce a 100 watt amp to 25 watts, is pull two tubes (or otherwise remove them from circuit), then run the remaining pair in Triode, instead of Pentode. This is bassically what 30th Aniversary amps did.

[keano12]

Re: Old JCM800s

So basically with the 6550 the sound will get louder only, less distortion?

Are the new JCM800 2203 vertical or horizontal? And someone mentioned here on this thread when turning up the volume on this amp (forgoet reason why) that they cab thinner. Has this been fixed on the reissues?

Are there any EL34 that aren't as middy/hi end more low end like a 6550?

[keano12]

Re: Old JCM800s

By the way when I played a 100 2203x witha ZW OD it squealed like a pig would a boss noise supressor kill that?