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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
gdnrbob
4,457 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

fuzztone's avatar
fuzztone
5,634 posts
 
It’s just the cable co.
They have a different ground than your house does. Put a Ground Loop Isolator for Cable TV applications F Connector on the cable feed. I have a bunch I paid $8@. MCM used to have them but they’re gone.
Some are on eBay. Best $15 you will ever spend.
Nothin' to do with amps

oldhvymec
5,101 posts
 
Yup, I went through the same thing as fuzztone with a cable box, and Power supply.
15.00 usd fixed like new, with a great little GL gizzmo. 3 or 4 (options) one was with a wire added to one of the devices, I didn't have to use it..

Safety first, protection second. I always protect MY expensive gear.
I have NEVER suffered SQ loss.

Great power supplies, in equipment go a long ways. Krell, Mcintosh. Pass, and a few others don’t squeeze where it REALLY counts, the Power supply. A ZERO noise floor for me...

A little test....

TURN the volume ALL the way up with nothing playing, on your vinyl rig, SDAC or something.. Is there ANY noise? No noise, you did a good job.. It’s hard to do for some folks.

A LOT of  listeners just say I can't hear it when it's playing so what's the difference... I guess it's just me.. I'm picky, REAL PICKY.  Even my 600.00 special system had NO noise, FINALLY.. Took a day or two..

Regards
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