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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
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.
jea48
4,400 posts
 
http://www.jensen-transformers.com/an/an004.pdf

http://www.jensen-transformers.com/an/generic%20seminar.pdf
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b_limo's avatar
b_limo OP
2,274 posts
 
Xti 16,
Thanks for the reply! I was also told that I could try getting a cheater adapter thst goes from a three prong to a two prong, but I've also heard not to do that, as it may be dangerous?

Jea 48,
I stumbled upon that very site lastnight. It was a little above my head, but I'll read it again and try to figure it out! Thanks.
xti16
1,525 posts
 
A cheater plug is the same as lifting the ground. Normally it isn't a problem. Key word is normally. When I had the problem I could lift the ground on either the Bryston or my Meridian G08. I chose the G08 because is has the lowest current draw. That was something I was taught when I worked for TI with very large 'current' draw devices in computer systems (yeah the big 250 lb 25 mb disc drives). I even tried using a 2KVA isolation transformer with a balanced output. It cut the hum down a hair but also changed the hum to a buzz. I think the Xlr's is the best choice.
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