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Ground loop feedback - cable wire issue

After installing an amp there was a ground feedback low hum noise. Muting ht system made it go away but not a good solution. Also, routed cable thru surge protector and this substantially reduced problem, but still slightly there. I don’t like using surge protector.

cable co came and grounded cable wire. But this did not solve problem and I still need Cable wire to go thru surge protector. Outlets in room all controlled by one circuit. All components except tv and amp share a surge protector. Tv goes thru power conditioner and amp plugged directly to wall.

disconnecting cable wire eliminates feedback noise, even after being grounded.

Seems amp related, not sure why.



emergingsoul

Showing 2 responses by gdnrbob

gdnrbob
4,495 posts
 
I have had this issue with my office.
I even sent my amps and preamp to Atmasphere to sort it out, but, to no avail.
It seems some amps don't play well with other equipment.
I think it might be some inherent design issue with the amp, but I am no EE.

Have you tried a 'Hum Buster' or tried to float the ground on the amp?
Bob

gdnrbob
4,495 posts
 
To lift a ground means you remove the ground pin.
You can do this by either removing the ground pin from the plug (not recommended), or using a ground cheater:
https://en.wikipedia.org/wiki/Cheater_plug.
As your Marantz has only 2 prongs, then this is moot.
I will defer to atmasphere with regard as to how to proceed.
He looked at my equipment when I had a similar issue.
Bob
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