The hum is present through all five speakers evenly. I have tried a cheater plug in every configuration possible. The external ground although not very safe does not change anything. The ground to the house is good and so is the run to the receptacle. As I said I tried several receptacles throughout the house and it was no better, infact worse for the most part without the panamax to filter. Remember the hum was not present in the four amps I had before. Thanks for the sugestions I guess I just wasn't meant to own a Cinepro.
Help amp hum is driving me crazy
To start with I have a B&K ref20 pre with Polk SRT speakers. I have Kimber Monacle XL and 8tc for speaker wires and Phoenix Gold RCA cables. I use a Panamax 1000 and a DBS for protection. I had a Sunfire CG with no problems but felt I needed more explosive power for home theater so I bought a used Cinepro 3K6 II. It hummed like crazy at first (50db). So I began the sytematic aproach, I started unhooking items looking for the culprit. I eventually ended up with just an amp hooked to speakers, still humming. I tried an extion cord plugged into several other outlet in the house, some worse none better. The Panamax DBS works the best at filtering out the most. I tried cheater plugs in every combination I could think of to no evail. The ground lift switch on the Cinepro helps very minutely. I tried different interconnects. What else can I do besides get rid of it or spend thousands on filters I never needed before? I am an electrician and would like to think I am fairly well schooled but I feel like an idiot.