Music Man 2165-RD Voltage Issue

[stereomonostereo]

Hey all. I'm working on a Music Man 2165-RD (Transistor P.I.) that sounds less than pleasant. I've checked some voltages, and I'm only getting 480VDC at the plates of the 6L6's. On a regular amp, that's normal, but the Music Man calls for 700VDC. I have the amp set on high power when I'm taking the reading. On low power I get 325VDC. When testing at the standby switch, I'm only getting 122. On the other side of D11, I'm reading the 480VDC.

Sound like a power transformer issue?

[g1]

Being a voltage doubler circuit the caps are quite critical. I would suspect them before the x-frmr. Assume you have checked the diodes?

[stereomonostereo]

Being a voltage doubler circuit the caps are quite critical. I would suspect them before the x-frmr. Assume you have checked the diodes?

I have checked all the diodes and they all read okay. I'll check the caps once I get back into the shop tomorrow. I'll let you know what I find. Thanks!

[stereomonostereo]

Being a voltage doubler circuit the caps are quite critical. I would suspect them before the x-frmr. Assume you have checked the diodes?

That did the trick. Thanks!

[drewl]

Might want to replace the diodes anyway since they're cheap.
I know I've been seeing alot of Mesa's with the DC filament rectifier diodes failing BUT still reading okay with a meter.