I received this Music Man HD-130 amplifier with the complaint that it hums.
The four output tubes are 5881WXT. The owner replaced the two main filter
caps himself and said it didn't correct the problem. When I opened the unit
and found one of the yellow wires hanging loose from one of the filter caps,
I soldered it to the other yellow wire which was connected to the filter
cap.

See photos he

http://www.pbase.com/image/57610175.jpg
http://www.pbase.com/image/57610176.jpg
http://www.pbase.com/image/57610312.jpg
http://www.pbase.com/image/57610174.jpg

Now the amp is drawing too much current at idle and I definitely need to
check the wiring to the filter caps. I don't service many tube amps like
this. Does anyone have a schematic of this set? I tried the ernieball.com
website but it's not listed there.

Thanks for your reply.
--
David Farber
David Farber's Service Center
L.A., CA