Question about Adcom GFA-5503 3-Channel Amplifier

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Lots of hum from both speakers

I'm getting a lot of hum and buzzing on both speakers making quiet passages in music less than quiet. I have checked any possible power cord interference without any effect. The hum begins when the Adcom is turned on and only diminished after the pre-amp is started. Still, it is too loud to be exceptable. Any suggestions?

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Well folks I solved my problem and the amp has never sounded better. It had always hummed and now it close to stone quiet. The secret was it really never a problem with the amp. The problem was the result of either the pre-amp, interconnect cables, or the combinations of them. The solution came when I added a "drain wire" or ground to the cable I was using. There must have been a ground loop or some in-balance that required a wire to be connected to the earth (-) side at the source on the interconnect and then left unconnected at the other or receiving end of the interconnect. Anyway, no more hum, and the solution took some spare wire and solder.

Posted on Nov 23, 2008

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