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McIntosh Transformer causing noise in speakers while disconnected.

Regarding General Noise: On top of the things I've been working on, I am also suspicious that I have a grounding issue somewhere. I get a definite 60hz noise/buzz when I plug in the RCA interconnects. This was previously unnoticeable because of the noise from the amp, but now that that is better, a new noise has become apparent. There is a little noise from the speaker cables, but the interconnects introduce the most noise at this point soon as they're connected from AVR/PRE to Amp.
Sounds like a ground loop. The best solution is using balanced interconnects but I don't think that is possible in your situation with your current equipment. I have had similar issues and you can try a lot of things but when you are mixing anything connected to cable TV or Satellite with other Hi-Fi gear ground loops are almost inevitable as the TV source ground is different than the mains ground. The only reliable solution I have found is a transformer based isolator like this https://www.jensen-transformers.com/product/ci-2rr/ . These are a little expensive and people try to avoid them but they work perfectly in most cases and the silence they provide is very welcome.
 
Sounds like a ground loop. The best solution is using balanced interconnects but I don't think that is possible in your situation with your current equipment. I have had similar issues and you can try a lot of things but when you are mixing anything connected to cable TV or Satellite with other Hi-Fi gear ground loops are almost inevitable as the TV source ground is different than the mains ground. The only reliable solution I have found is a transformer based isolator like this https://www.jensen-transformers.com/product/ci-2rr/ . These are a little expensive and people try to avoid them but they work perfectly in most cases and the silence they provide is very welcome.
I'm not using cable TV or satellite. It's advice still the same?
 
@ClassG33 have I asked if you are using parametric EQ with your PC source? I ask so many peeps that sometimes I forget. :D
 
What kind of rca cables are you using?
Audioquest Yukon cables.
I have custom made RCA > XLR on order from them, curious if that will do anything. I feel like they could increase the noise possibly. If the rca>xlr conversion doesn't help anything since it's technically still imbalanced, the input sensitivity with balanced inputs is higher.
 
Audioquest Yukon cables.
I have custom made RCA > XLR on order from them, curious if that will do anything. I feel like they could increase the noise possibly. If the rca>xlr conversion doesn't help anything since it's technically still imbalanced, the input sensitivity with balanced inputs is higher.
I don't know that the Yukon cables would be a problem. Try some cheap RG59 or RG6 based RCA interconnects. If you have some RCA video cables laying about, that is how they are usually made. They'll shield the connection as well as can be done with RCA. RCA will not be as quiet as balanced in some environments.

Something like this:

I don't know what custom made RCA to XLR adapter you are getting, but those sometimes work just fine from Monoprice. Make sure you get the right gender.
 
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I'm not using cable TV or satellite. It's advice still the same?
Yes, still sounds like a ground loop to me ... you don't need cable or satellite to create a ground loop but they tend to make it worse. Jensen also makes "real" RCA to XLR transformer based adapters which provide galvanic isolation between components. You may be able to get it to work without it but in some cases I could not and the transformers were an instant and complete solution to a problem I spent a huge amount of time and effort to solve.
 
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Yes, still sounds like a ground loop to me ... you don't need cable or satellite to create a ground loop but they tend to make it worse.
Hi @levimax. Can the chassis(s) of the equipment be connected via alligator clips for a test to see if positive results occur? Are there floating chassis(s) at play here?
 
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I don't know that the Yukon cables would be a problem. Try some cheap RG59 or RG6 based RCA interconnects. If you have some RCA video cables laying about, that is how they are usually made. They'll shield the connection as well as can be done with RCA. RCA will not be as quiet as balanced in some environments.

Something like this:

I don't know what custom made RCA to XLR adapter you are getting, but those sometimes work just fine from Monoprice. Make sure you get the right gender.
Not an adapter, just a cable with rca on one end, xlr on the other. Audioquest will make custom made cables like that upon request.
 
Hi @levimax. Can the chassis(s) of the equipment be connected via alligator clips for a test to see if positive results occur? Are there floating chassis(s) at play here?
Ground loops are a simple concept but can manifest in ways that hard to understand and isolate. Part of the problem is some modern devices have digital grounds seperate from video grounds seperate from audio grounds and then floating vs grounded on different devices. I have had some luck connecting the chassis together, usually it is recomended to use heavy gauge wire so alligator clips might not be a good test but would be an indication. One time I connected the cable TV ground to the mains ground and it solved the ground loop problem. I do not understand all the safety ramifications of doing that so I bought a cable isolator which also solved the problem. Balanced connections make all the guess work and noise go away.
 
It's

Not an adapter, just a cable with rca on one end, xlr on the other. Audioquest will make custom made cables like that upon request.
That is what the Monoprice cables I linked above are. Usually they just tie the inverse pin of the XLR to ground and usually that is enough. Sometimes it is not and as Levimax has said the Jensen transformers will do the job. There are ways to load the inverse pin on the XLR to ground thru resistance and improve the situation some. If the custom cables are costing as much as the Jensen solution you'll be well advised to get the Jensen's instead.

As others have noted that 60 hz hum and getting rid of it can seem like a black art at times. If analyzed carefully, you can figure out why, but in practice it can seem like voo doo.
 
@ClassG33 I just looked at the cost of Yukon cables. Don't do that. I'll be blunt. You can get the Jensen isolation transformers far cheaper, and they will work. You can get them that isolate ground loops in an RCA to RCA configuration.

Here is the RCA version. You'd want to keep this ISO unit close to the amp and use a short cable between it and the amp. The input side cable can be rather long.


You can get them here for $240 for both channels ($120/channel) and keep the cables you have.
 
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Balanced connections make all the guess work and noise go away.

Usually. There was a thread here where I explained how my Yamaha CX-A5100 and Meyer Sound Amie’s generated a ground loop despite running XLR cables and being plugged into the same power strip. This was solved by grounding the CX-A5100 to the power conditioner’s ground lug.

More technical members were able to explain why since the Meyer had a virtual ground lift approach and the Yamaha had an unusual ground strategy too.
 
the problem is some modern devices have digital grounds seperate from video grounds seperate from audio grounds and then floating vs grounded on different devices.
So complicated and sophisticated. :D
 
@ClassG33 I just looked at the cost of Yukon cables. Don't do that. I'll be blunt. You can get the Jensen isolation transformers far cheaper, and they will work. You can get them that isolate ground loops in an RCA to RCA configuration.

Here is the RCA version. You'd want to keep this ISO unit close to the amp and use a short cable between it and the amp. The input side cable can be rather long.


You can get them here for $240 for both channels ($120/channel) and keep the cables you have.
I've already had the yukons. I am getting the new custom cables at dealer price so it's actually gonna be much cheaper, but I definitely am gonna get the Jensen piece as a past resort.
 
@ClassG33 I just looked at the cost of Yukon cables. Don't do that. I'll be blunt. You can get the Jensen isolation transformers far cheaper, and they will work. You can get them that isolate ground loops in an RCA to RCA configuration.

Here is the RCA version. You'd want to keep this ISO unit close to the amp and use a short cable between it and the amp. The input side cable can be rather long.


You can get them here for $240 for both channels ($120/channel) and keep the cables you have.
Plus I would need it for three channels but I read up on these services and ppl swear by them, so I'm really glad you recommended it. I'm probably gonna get them either way for my recording studio!
 
Plus I would need it for three channels but I read up on these services and ppl swear by them, so I'm really glad you recommended it. I'm probably gonna get them either way for my recording studio!
I got up and dug mine out. The main cause of ground loops is using multiples outlets for the gear. I had used it to run something from one room to another and it worked great. https://www.amazon.com/gp/product/B01A56CMUO/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
 
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