O100JM transformer in a 2203

HIn · Post by **HIn** » Sat Jan 20, 2007 12:49 am

Would a MM 0100JM transformer work as a replacement for a marshall JMP 2203 amp.

Guitar Adjuster · Post by **Guitar Adjuster** » Sat Jan 20, 2007 10:53 am

Dont' know about the MM but I used George's clone Heyboer in a 2203 and it sounds great, better then the original 80's 2203 tranny. I would guess the MM would sound equally as fine.

Post by **VelvetGeorge** » Sat Jan 20, 2007 11:55 am

The O100JM does sound great in a 2203. There is also a O100JM-M that is tweaked for higher gain and works with 6550's and KT88's.

george

joshwilson3 · Post by **joshwilson3** » Sun Jan 21, 2007 1:28 am

Flames1950 · Post by **Flames1950** » Sun Jan 21, 2007 8:07 am

"Marshall" never put a different output tranny in for 6550's, and in fact "Marshall" never put 6550's in the amps of their own accord anyway -- the distributor forced that upon them. And it's not real clear whether Marshall even did the conversion for the distributor -- most books make it sound like the distributor did the changes themselves but I don't know if that is true or not (I wasn't there.

)

Post by **VelvetGeorge** » Sun Jan 21, 2007 5:55 pm

AFAIK, the 1.7-1.8K primary impedance has not changed since the Dagnall 1.5" OT's started showing up in late '67. So there was not a change for 6550's.

VG