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AC-30 Ghost notes - still....

8/14/1999 4:30 PM
Pat FAC-30 Ghost notes - still....
This is an old question revisted. My AC-30 clone is still giving me ghost notes when pushed into OD. Last time I posed this problem, I got recommendations to check filter caps, ground loops, different speakers, pretty much the gamut of normal things to look for. I've got the plate supply filter up to 44uf now. The amp is completely star grounded except for the speaker output, and an adjustable line out jack that are not isolated from the chassis. I've checked all the other obvious things, the output current is dead on. I swapped out the entire set of tubes, including a full set of matched EL84s. I've tried several different speaker cabinets/types, different guitars. The only thing that moderates the ghosting a is adjusting the tone, backing off on the bass a little.  
I'm getting ready to carefully ream out the speaker and line out jack holes (alot more difficult to do on a fully assembled chassis) to isolate them from the chassis as my last effort to illiminate them as the source of the problem. But before I do, I'd like to hear from anyone who might have an idea of something I've overlooked. I have a guy who is interested in buying this amp, but I don't want to sell something that I personally am less than satisfied with. Any pointers are appreciated.

Bruce Sounds like you've tried all the no... -- 8/15/1999 5:25 AM
R.G. Another question made me think of t... -- 8/16/1999 2:23 AM
Mook My thought is the speakers. Are th... -- 8/16/1999 1:34 PM
Gus Are the power supply IC brand caps ... -- 8/16/1999 2:02 PM