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unusual noise

 :

10/12/2004 3:35 AM

joe6v6

unusual noise My amp makes a noise that isnt teribly offensive but it is somewhat bothersome and I would like to find out what it is just for my own peace of mind.     When I play cords or single notes agressively for more than say 10 or 15 seconds after I stop playing 2 or 3 seconds later I hear 2 distinct pops thru the speaker, they arnt as loud as whatever volume I happen to be playing at but they are there. they are more like thuds or thumps than pops. these two same exact noises happen when I turn the amp on for the first time. power switch on wate 20-30 seconds sdandby switch on and 2 or 3 seconds later " thump - thump " no more no less always 2 times. other than that the amp sounds great and operates perfectly.     I can live with this noise I would just like to know if its causing any damage or maybe a part is bad. , , , Thanks for the help ; JOE

 

10/12/2004 4:14 PM

Brutus

Just a guess...     Maybe your PS filter caps are not rated for the high voltage you have on them. That might explain the pop when you turn on the HV. And when you play hard for 10 secs your PS starts to sag lowering the voltage. When you stop playing the sag drops and the HV once again maximizes perhaps causing a pop.     This is just what comes to mind. Are your filter caps rated for the voltage you are using? I've also had pops in an amp which I used 400v signal coupling caps where 450v was present. The caps never blew, but just poped alot. In my case I think it was just metalized film caps going through a self healing process.

 

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