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previous: Benjamin Fargen Chip:As always, try replacing t... -- 2/8/1999 10:06 AM View Thread

Re: Loud hum.....Help!

2/8/1999 11:00 AM
Re: Loud hum.....Help!
Thanks for the response, B.F.  
I swapped out the power tubes. Didn't help.  
Replaced the FB resistor - no change.  
Am checking solder joints/grounds....  
Add'l info:  
Hum occurs with or without guitar plugged in.  
Amp works fine, it's just that hum is always present (it's almost as loud as the guitar signal...).  
Removing all preamp tubes stops the hum.  
The hum gets progressively louder as preamp tubes are replaced, going from PI to input order.  
Since the problem started while playing through the amp, it seems logical there must be a component/connection failure somewhere. Thus far I can't find it, however.  
Also of note, this amp has one of those round, British power cable connectors. It's never been a particularly snug-fitting connection, and wggling it does create some static. But then again, it always has......  
Any other ideas where to look?  
Thanks again......  

Graywater Chip:Power supply hum in al... -- 2/8/1999 11:06 AM