Question about Marshall JCM 800 4212

Re: Question about Marshall JCM 800 4212

Try the amp out. Some people don't like the diode clipping, but some do (Can you say "Tom Morello"?). It's a good solid amp that has not taken off in value like some others.

If all else fails, it's a great mod platform - lots of tube sockets that can be re-wired without punching holes.
 
Re: Question about Marshall JCM 800 4212

One other thing I forgot to mention, it's got 2 6550's. Can this amp take EL34's? And if so what kind of difference tonewise will switching tubes make?
 
Re: Question about Marshall JCM 800 4212

Yes, it can take EL34's, but rebiasing it might require a little bit of component-swapping. Any competent repairman can do it for you.

And send me those 6550's. I don't need an amp powerful enough to use 'em anymore, but I'm dying to make a set of bookends for my office, complete with light-up filaments.:dance:

Edit: corrected tube number in first line.
 
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Re: Question about Marshall JCM 800 4212

I play through one, and i believe Jeff_H has a modded one too. I love the sound of mine, and many people have told me this amp can sound great with a few mods, but i honestly don't feel i need them. Definately try it out, mine is the perfect amp for me and i wouldn't swap it for anything. There are alot of mixed opinions about these amps, but i can't say enough good things about mine, love it.
 
Re: Question about Marshall JCM 800 4212

Forbes said:
I play through one, and i believe Jeff_H has a modded one too. I love the sound of mine, and many people have told me this amp can sound great with a few mods, but i honestly don't feel i need them. Definately try it out, mine is the perfect amp for me and i wouldn't swap it for anything. There are alot of mixed opinions about these amps, but i can't say enough good things about mine, love it.

Yes he does, kinda purty......

1_0422.jpg


Jeff Seal
 
Re: Question about Marshall JCM 800 4212

Jeff Seal said:
Yes he does, kinda purty......

1_0422.jpg


Jeff Seal


Pretty! I've heard that you did a great job on that one Jeff!
 
Re: Question about Marshall JCM 800 4212

Is that the inside of a 4212? That does look nice. Is it a point to point amp?
 
Re: Question about Marshall JCM 800 4212

Please Jeff- what mods do you have for a 4211?

As far as Diode clipping, most users of a JCM 800 use a tube screamer, DS-1 in front of it, and those have diodes, so I wouldn't discount a JCM 800 because of the diode clipping
 
Re: Question about Marshall JCM 800 4212

Iceman79... the picture is of an '87 4210 that I modded for one of the forumites here.... It originally has a PCB that's mounted to the front of the chassis. When I mod these, it's much simpler to convert it to PTP as opposed to "permanently" altering the original PCB. This allows for the amp to achieve whatever the customer desires, but still allowing the amp to be be converted back to original.... I do not ever, ever, ever!... drill holes in amps and the 800's have a considerable "vintage" value that has to be considered...this way, if it doesn't come out sounding like you want....no permanent modifications have been done....

jmh151... mods for these range from simple to extreme.... depending on which one you have and what you're after!

I have run into a slight problem with the short(not as wide as the head version) chassis combos, as some combinations cannot be achieved, given the smaller "area" in which to fit some circuits.... V!n has one of them, and I'm trying to figure out a way to make circuits that will "bolt in" instead of having to ship the whole chassis here....still haven't gotten there yet. (V!n's been waiting for almost two years...:blackeye: and we have had to abandon some original ideas since he has the short chassis..)


Jeff Seal
 
Re: Question about Marshall JCM 800 4212

Ok, finally went down to shop w/my guitar and checked it out. Sounded great with my Dipinto, sounded amazing with my friends Ampeg Dan Armstrong. It nailed the Black Flag sound easily with the Ampeg and with my Dipinto I was in Stooges/MC5 territory. However, to get "the sound" it has to be cranked, which is ok because I got my Zinky for bedroom jamming. One last thing, someone told me that this amp can also take KT88's, is this true? Would it be a direct swap?
 
Re: Question about Marshall JCM 800 4212

<homer voice>mmmmm, Zinky Blue Velvet. :32:</homer voice>

I LOVE those amps.
 
Re: Question about Marshall JCM 800 4212

Looks like you used mylar caps in that amp Jeff - have you tried Sozo caps? They're supposed to be the best in the market by far for Marshalls.
 
Re: Question about Marshall JCM 800 4212

Jeff Seal said:
V!n has one of them, and I'm trying to figure out a way to make circuits that will "bolt in" instead of having to ship the whole chassis here....still haven't gotten there yet. (V!n's been waiting for almost two years...:blackeye: and we have had to abandon some original ideas since he has the short chassis..)
True, very true .. :2:
 
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