Transformer Question: JCM 800 vs Plexi

red5 · #1 03-22-2006, 09:44 PM

Okay so really soon I'm going to pimp out my JCM 900 SL-X. RFT 12AX7s, EL34 tubes although 5881s is still a thought....

What I am trying to decide now is should I drop a jcm 800 era transformer which is slightly brighter or the older, plexi transformer into the amp which is meatier?

I was really learning towards the 800 era but then I thought about it. I have 4 12AX7s and loads of preamp gain which is what the amp is for, so with the extra preamp gain it should be bright enough anyway so I might as well get a plexi tranny.

It might come down to a coin toss other than what you guys recommend..

Ant1981 · #2 03-22-2006, 10:06 PM

How will the transformer being changed make any difference in sound when all a transformer does is change the voltage?

red5 · #3 03-22-2006, 10:48 PM

Quote:

Originally Posted by Ant1981

How will the transformer being changed make any difference in sound when all a transformer does is change the voltage?

OTs make a huge difference in sound. PTs are fairly insignificant.

The OTs in the newer Marshalls are quite harsh and thin. Replacing the transformer in a plexi reissue will make that reissue actually sound almost like the real thing, but stock they are far from it.

Earthrug · #4 03-24-2006, 01:21 PM

Get a MIG-60. They are cheap and already sound like a suped' up Marshall.

red5 · #5 03-24-2006, 10:44 PM

Quote:

Originally Posted by Earthrug

Get a MIG-60. They are cheap and already sound like a suped' up Marshall.

Already have the SL-X though.. it was between modding a 800 for gain or the cheaper method of the SL-X and work backwards from there. Either way I'll end up where I want to be

Ant1981 · #6 03-24-2006, 10:47 PM

I just find the 800's to be a bit bright sounding, especially clean. You can have mine if you want, it has Drake transformers

red5 · #7 03-24-2006, 10:58 PM

Quote:

Originally Posted by Ant1981

I just find the 800's to be a bit bright sounding, especially clean. You can have mine if you want, it has Drake transformers

You have a 2205 or 2210 right? There is a huge difference between a 2205 or 2210 and the 2203/2204 models, and a significant difference between earlier models ('81-'83) with vertical inputs vs the later ones. The earlier ones weren't so bright sounding although a tad brighter than the earlier JMP era 2203/2204s.

A 2205/2210 would be way to much to mod to be a 4 tube Marshall. ;P

Ant1981 · #8 03-25-2006, 09:55 AM

I just love the way the 900's rock tho. But yea mine is actually the combo version of the 2205 i think. It's 50w anyhow.

red5 · #9 03-25-2006, 02:03 PM

Yeah 900s are rougher because the cheap trannys than a 2203 but not all that much brigher as opposed to the later 800s which are my 2nd least favorite all tube Marshalls (IMO).

Ant1981 · #10 03-26-2006, 11:06 AM

No I think you misunderstood. I was saying my 800 sounds rough, not my 900. There is nothing wrong with my 900, it sounds superb, warm and great tone.

red5 · #11 03-26-2006, 03:13 PM

900s sound rough with cleaner pickups. With Evos however *drool*. I was also comparing to a 2203/2204 though where ya yours is a bit rougher.

Gresh · #12 03-26-2006, 09:12 PM

Definitely go with the plexi spec OT. Who's doing your mods? I had a Marshall modded by Voodoo amps years back, plexi OT and bunch of other tweaks...insane tone.

red5 · #13 03-26-2006, 10:00 PM

A guy from Connecticut named Ted Dreger. He did the work on my Marshall Major and did an excellent job I must add.

Did you ever look inside your amp? Apparently ****head from voodoo covers all his connections in an apoxy so if you ever need that thing recapped it's gonna cost you and would probably be easier to rebuild the amp. I do hear he does nice work though!