ampage Tube Amps / Music Electronics	For current discussions, please visit Music Electronics Forum.

ampage archive

Vintage threads from the first ten years

JCM 2204 and OEI 50W OT.

:

4/18/2003 5:31 PM
johnr	JCM 2204 and OEI 50W OT. I'm jonesin to try this on my amp. If you've done this,how did it sound after the swap?Was the improvement in cranked tone impressive? I'd like to try this with my JCM2204.The amp is a 1986 Vertical input(yes!)Canadian Marshall with a stock Drake OT. The amp does sound good,but,maybe it could even be better?.I've modded the preamp to my satisfaction. thx everyone john

4/19/2003 11:26 PM
johnr	Re:OEI sound? ok ,not a hot topic,too many jcm800 q's on tap on the board i suppose...nevertheless,i want to find out,so,i'll make the change and post my opinion here once i've completely checked it out... jr

4/20/2003 12:28 AM
Chris ( CMW amps )	Hi John The OT is the part of the amp that does "connect" the tubes to the speakers . I've heard the OEI OT in several Marshall amp and it does give you THAT great Marshall Plexi sound Chris All transformer(-symbols) do look the same at a schematic but they all sound different LOL

4/22/2003 8:06 PM

Re: JCM 2204 and OEI 50W OT.

quote:
"I'm jonesin to try this on my amp."

I heartily reccommend the OEI Plexi OT!

I have a AB165 Bassman that I gutted and rebuilt as a 2204-like circuit, and it sounds ***much*** better with the OEI Plexi unit than it did with the original Fender OT (wanna buy a '65 Bassman OT?

). It sounds like a good old Marshall should, which is nice, considering the more "modern" '80s Marshall preamp topology it's using....

HTH!

C ya,
Dutch

4/22/2003 9:23 PM
SLObrain	Dutch, I did that same thing years ago and the OT from the bassman had a good tone but if I were to do this again I would probably use a Marshall replacement OT as well. BTW what did you do with the extra 12AX7 you had left over? It would make a good FX loop tube. SLB

4/29/2003 3:39 AM

quote:
"BTW what did you do with the extra 12AX7 you had left over? It would make a good FX loop tube."

SLB--

It did. The best all-tube loop circuit I've ever built.

I set my Bassman head up for "channel" switching between two different gain and volume pots, so that I could get two different sounds out of it--cleanish and dirty.... The cleanish "channel" has use of the bright and deep switches to add a little bit and keep it from sounding too thin and middly.

One of these days I'll get an up-to-date schemo of it on my web site.

C ya,
Dutch

4/25/2003 11:44 PM

I did it a while back and learned yet another lesson...if your 2204 has any mods in it, strip them out now and return the amp to stock before adding the OEI. Forgive me Joe...

The midrange is different and more plexi in the sense of Cream live tracks. In comparison, the orignal Drake makes for a brighter and thinner sounding amp -- not that you'll run out of treble though. You end up dialing in more when your done.

Page 1 of 2