2. home-theater
  3. 166032-126

Eliminating Ground Loop Problem

I use a Marantz 7702 MKII processor, ATI 3-channel amplifier to drive my center and rear channels, and my Jeff Rowland Corus preamp with HT bypass when watching movies. I'm using RCA interconnect cables from the Marantz to the ATI, tried balanced XLR cables with no change. I contacted Marantz and they didn't provide any advice. ATI helped me troubleshoot the issue and we isolated the problem to the Marantz. Any advice on how to eliminate the ground loop issue? 
ricred1
oldhvymec
5,101 posts
 
There you go OP, Everything has to be plugged into the same circuit and after you verified that by turning on something ELSE, the noise came through the center and rears.. It sounds like they are on a different leg at the main..

One circuit
Unplug routers and PS to laptops
and do some cable art.. My system is dead quiet.. 65 year old C20 preamp point to point.. Talk about an antenna.. LOL Zero noise..

Quiet as a mouse.. Valves in all, there are a slough too.. 30 valves in my system... Quiet as a mouse.. 7 per preamp (2 C20s) and 16 in the ol Cary V12R
mcroth
81 posts
 
My oppo did the same thing with HDMI. Never could get rid of it, so I lifted the ground on the Oppo.  But beware of the grounding police.
ricred1 OP
2,055 posts
 
Everything is plugged into a Torus RM20. I don't use a laptop. My 2-channel is quiet as a mouse. The noise only occurs when I'm using HT.
Post removed 
oldhvymec
5,101 posts
 
Ok I’m serious now.. I got a feeling If I routed that bunch of cables and inspected the connection including grounds between components, a LOT of the noise would go away if not all of it.
A crap cable can drive YOU nuts too. NOT ME though.. I won't stop until my system is quiet..

At least 10 times I’ve fixed system that supposed PROS didn’t fix because of routing.. You know the Stereo Only, kind of free install they get with a 20K purchase.. LOL.. They leave and you can hear arcing in the back ground.. as you tip them for their BAD work.. BUT you think it’s wonderful..

Can’t find the cat, see his tail sticking out from under one of your new 10k 200 lb speakers.. Still purring..

If the noise is that bothersome, it has to be routing at least partially..
I’m telling you you can stand by my speakers and turn the system up all the way, you have to be within 12" to hear anything.. I can hear valves hiss, ever so slightly.. My kids can’t hear it at all.. Grandson and wife can though.
A lot of valves, too.. 

Regards
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