I've got an Adcom GFA-555II running a passive subwoofer with two 12"'s. I've got the amp plugged into a Panamax 5510 pro power conditioner. When the power to the amp is turned on (speaker wires are all hooked up) it is totally quiet. But as soon as I plug the cable into the back of the amp I begin to get a hum in the sub, and this happens even if the other end of the cable isn't plugged into the pre-amp (Sunfire Theatre Grand III). Basically it is fine until the cable is plugged into the back of the unit. I do have the amp bridged to mono and the sub is a 4 ohm speaker so effectively its got about 700 watts going into it. Any ideas what the problem could be and how I correct it. I'm using an AudioQuest Ruby Red cable from the amp to the preamp. Help!!!
Sounds like a ground loop humming sound, try connecting a short wire attached to one of the screws on the side of the amplifier and place the end of the wire to another audio component to see if the humming cancels out as, I have come across this (Electronic Gremlin) many times over the years and the last time it was a buzzing EMI sound that took me around +30 hours to resolve the resolution...
Wonderful! That got rid of the hum! Now is there anything I can buy to permanently ground it without having to run wires everywhere. Also now when I plug the interconnect into my preamp (Sunfire Theatre Grand III) and I have the volume up to the level I normally listen to movies at I'm hearing ?static? from the sub. Sounds like a shhhhhhh noise. Any ideas for that one? I don't hear anything like that on my main speakers. Could it be the crossover from the preamp? T.H.D.?