Author Topic: Gibson GA-20 with BAD hum (Read 18449 times)

shooter · « **Reply #50 on:** February 21, 2015, 01:06:05 pm »

another shot in the dark, look at K's link for eliminating noise in amp tips n tricks - at this point who knows!

BigE · « **Reply #51 on:** February 22, 2015, 05:29:16 pm »

Resolved!!!

Finally got around to replacing the tube socket and that did the trick. Super quiet now.

Thank you everyone for your help and advice.

mresistor · « **Reply #52 on:** February 22, 2015, 06:12:03 pm »

Great news. Which socket was it?

BigE · « **Reply #53 on:** February 22, 2015, 06:18:59 pm »

The PI socket.

2deaf · « **Reply #54 on:** February 22, 2015, 06:38:29 pm »

I'll betcha the combined PI anode current is now about the same as the PI cathode current.

Willabe · « **Reply #55 on:** February 22, 2015, 08:55:44 pm »

Resolved!!!

Finally got around to replacing the tube socket and that did the trick. Super quiet now.

I'll betcha the combined PI anode current is now about the same as the PI cathode current.

Please check that out and post for us.

Brad

shooter · « **Reply #56 on:** February 23, 2015, 10:15:15 am »

Glad that worked, I've now swapped 4 sockets, all from amps about as old as me!

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Hoffman Amplifiers Tube Amplifier Forum » Amp Stuff » Tube Amp Building - Tweaks - Repairs » Gibson GA-20 with BAD hum

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