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Another Hum question

So I just noticed a slight hiss / hum coming from both speakers, both drivers in each. Left speakers hum is slightly louder. I disconnected everything from the amp and it's still there. The only way I've been able to get it to quiet down is by hitting the switch on the back of the amp from unbalanced to balanced, and then there's no hum, just a very very slight hiss from the tweeters that I could live with. The amp is a classe ca 150. Any thoughts? Thanks for any input!!
128x128b_limo
gregm
3,405 posts
 
Sounds like a grounding problem (hopefully) rather than a caps problem (not so good) since it goes away in balanced mode.
As to what to do about it... check your power cord and the mains plug. Failing that, I think you're better off speaking to a technician.
Of course the french explanation will prime over all of what any of us have to say.
b_limo's avatar
b_limo OP
2,274 posts
 
Xlr's fixed the hum :-)
xti16
1,525 posts
 
Xlr's fixed the hum :-)
Still sounds like a ground loop somewhere. I had the same problem when I had my Bryston. My brother in law had the same problem with his Classe cdp and Bryston and for him balanced cables resolved it. For me I had the B100 which didn't have balanced and lifting the ground from my power cord solved the hum until I switched to an Octave intergrated.
b_limo's avatar
b_limo OP
2,274 posts
 
So am I okay just using xlr's, or do I need to fix the ground loop problem?
xti16
1,525 posts
 
B_limo you should be fine. Only if you go back to rca will you need to address the ground loop.
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