HELP: how to eliminate speaker HUM?

First, this is not speaker hum but a ground loop hum in the electronics.

Second, there are devices that will stop the hum but not cure it. In other words, the ground imbalance remains, so it would be better to cure it than put on a band-aid.

From your description, it is coming on the signal with each IC and that suggests the hum is being generated in the preamp. What happens if you remove each of the input ICs to the preamp? That should isolate the input device that is causing the ground loop. Are all your input devices on the same AC line?

Kal

Kr4 is right, but add this: if your cable box is attached to your HT setup, a poorly/non grounded cable coming in to the house could cause ground loop hum. Very Common. At least try removing the cable box from the system.

Hey guys, thanks. After I posted, I took out the Rowland Capri preamp from my HT system (had used for 2 chnl)and that did the trick for all speakers except for the sub. The sub has had hum for a long time, and has been plugged into a Monster 5100 PC and now a separate dedicated Furman. Don't know what the deal is with the sub, however, disconnecting the sub's IC eliminates the hum.