Music Man 112 RD-100

[Northernpike]

Longtime lover of Music Man amps.

I've worked on and played nearly every model.

I recently picked up this 112 RP-100/2100-RP that needed some repair. The amp produced a faint signal.
I opened the amp to find an arced power tube socket, an open 1K screen resistor, a few mods and leaky caps. Upon further inspection, I noticed a leg on the JE1692 transistor was broken and that both 3.9 ohm 5% emitter resistors had drifted to nearly 15 ohms.

I've replaced electrolytic and installed new 2N6488 output transistors.

Does anyone recognize this circuit? It seems like hybrid. Does it use EL34's or 6L6s? I ask because the don't believe the 1K screen resistors in the original circuit.

Any help would be appreciated.

https://www.flickr.com/photos/342583...57690689551891

Thanks,
Tom

[The Dude]

Here's the schematic for your amp. It shows 6CA7's.


http://www.pacair.com/mmamps//schema...nd_2100-rp.pdf

[Northernpike]

R58 shows a 3.3K resistor. There was a 1K resistor in mine.