Hanaleimike,
I'm a little late to this discussion, but anyway, here is a question for you:
When you said: " I would think that if each receptacle has it's own run via a 12/3 wire , all the way back to the panel on a separate ground bar in the panel, that there couldn't be any ground loops. I think the ground pin in the receptacle runs back to the panel, and the receptacle itself is grounded to the metal box. It sure made a difference sound wise too."
Specifically " separate ground bar in the panel"- did you mean, that there is supposed to be a separate ground bar for each dedicated line?
I understand, there is only one ground bar in the panel. Could you please explain that in more details?
I always been somewhat confuzed about the term "isolated ground"- isolated exactly how?
The reason I'm asking is this;
I have licenced electrician to install separate panel with five dedicated lines connected to it:
One for digital,
one for analog,
two for power mono blocks,
and one for video projector
He used Romex 12/3 wire, and to my understanding, at least, that's how I asked him to do it, ground wire from each receptacle (actually there are two receptacles on each run of wire) is connected to a ground bar in the panel, and the ground bar is connected to a copper ground rod right next to the panel, and to a common house ground elsewere.
Still, I have a ground loop problem somewhere.
Even when just a power amps connected to the speakers, and nothing else connected to the amps, and with grounds lifted on both amps with a cheater plugs, still I hear faint hum (much louder with no cheater plugs).
I have tried everything:
Unplugged every piece of equipment, and turned off all circuit breakers,
Lifted grounds on every single piece,
There is no cable, or TV on the same circuits,
Disconnected copper ground rod, installed along with the new lines, from the panel-
still, there is ground loop somewhere.
Now, I suspect, there is something wrong with how the ground wires from the dedicated lines are connected to the panel.
Unfortunately, I don't know of any audiophile electrician in my area, who could sort out the problem, and my "regular" electrician apparently has no clue.
Please, could somebody explain how to correctly ground my five dedicated lines, and how exactly "isolated grounds are created?"
Thanks in advance.
