Ground loops and powered speakers.

[TNPFan]

After trying several configurations, I believe I have traced my issue to the Oppo UDP-205 DVD/CD player. I am thinking it is just something with Oppo decks in general because I also have an Oppo UDP-203 and it does the same thing. When I use the cheater plug on either of the Oppo decks, the hum is significantly reduced. I have sent an email to Oppo customer service asking for their input and whether or not this is a known issue.

A big "Thank You!" to everyone who has taken time to lend your expertise and offer ideas.

 

[JayGilb]

After trying several configurations, I believe I have traced my issue to the Oppo UDP-205 DVD/CD player. I am thinking it is just something with Oppo decks in general because I also have an Oppo UDP-203 and it does the same thing. When I use the cheater plug on either of the Oppo decks, the hum is significantly reduced. I have sent an email to Oppo customer service asking for their input and whether or not this is a known issue.

A big "Thank You!" to everyone who has taken time to lend your expertise and offer ideas.

Glad to hear you have made good progress. There is no one solution for ground loop problems and often lots of trial and error is required.

 

[TNPFan]

Happy to report I found a suitable solution. Turns out both of my Oppo players both have ground loop issues - at least, they do in my system. I found a ground loop isolator online, gave it a try and problem solved. It works so well that the skeptic in me disconnected and reconnected everything a couple of times just to make sure it really works, and it does. Here is a link for more info on the device just in case anyone else is having a similar issue. (Hopefully, I am allowed to post URLs.)

Hum Exterminator – Morley

Looking for a Solution to Hum and Buzz in your Amplifier? The Hum Exterminator Makes Audio Hum Removal Easy through your Power Cable.

www.morleyproducts.com

Again, I want to thank everyone for their input, patience and tenacity to help me find a solution. Much appreciated!

 

[norcalscott]

FYI - I had an issue with a Polk powered sub and ground loop / hum when I moved the installation location. I took a chance on this product and am happy to report that it solved the issues completely and didn't seem to affect the sound quality:
InstallGear Ground Loop Isolator Amp Noise Filter
by RisingSteel Brands
Learn more: https://www.amazon.com/dp/B077Y5DLBB/ref=cm_sw_em_r_mt_dp_22MAJWN4A1WQ2JS7A29Y

At $10 this is a cheap solution for those applications in which it works.

 

[TNPFan]

I looked at one of those as well and decided I had to begin with one product or the other. Looks like we both solved a similar problem by approaching it at opposite ends. Ha! Glad to hear it worked for you. At $10, I may order the one you suggested just to see if there is any difference in sound with what I am using now. Thanks!

 

[marcheloka]

In the old days we had never a problem because all equipment had no mains ground. The stupid idea to start with mains grounding started was that it would sound better....

Almost all audio gear have an isolation class 2, no mains ground compulsory.

So if i remove the wire cable that is grounding, that yellow-green cable, will it solve my problems with awful noise? I got my laptop as a source and i connect projector with hdmi for a display and i connect powered speakers via RCA for audio. Then terrible noise appears and i think that might be ground loop. So i know XLR is better nad hum-free but i am looking for simplest low cost budget solution. Should i just demount electric sockets that go to proj, speakers and laptop and just unplug that grounding wire in all of them? Because i can do that easily

 

[antcollinet]

So if i remove the wire cable that is grounding, that yellow-green cable, will it solve my problems with awful noise? I got my laptop as a source and i connect projector with hdmi for a display and i connect powered speakers via RCA for audio. Then terrible noise appears and i think that might be ground loop. So i know XLR is better nad hum-free but i am looking for simplest low cost budget solution. Should i just demount electric sockets that go to proj, speakers and laptop and just unplug that grounding wire in all of them? Because i can do that easily

DO NOT REMOVE EARTH WIRES FROM EQUIPMENT THAT HAS THEM.

You will make the equipment dangerous, and potentially invalidate your home insurance.

 

[AnalogSteph]

I got my laptop as a source and i connect projector with hdmi for a display and i connect powered speakers via RCA for audio. Then terrible noise appears and i think that might be ground loop.

What kind of powered speakers exactly are these? Does the projector have a headphone output you could try?

As stated, do not mess with protective earth, it's called that for a good reason.

 

[Sokel]

What kind of powered speakers exactly are these? Does the projector have a headphone output you could try?

As stated, do not mess with protective earth, it's called that for a good reason.

Talking about earth connections,what's the deal with 60 or 80 Ohm RC circuits coming from PCB (isolated from case) to earth instead of a solid earth connection from PCB to case as usual?
I think I have seen that to a class D amp too,Purifi maybe?Or it was UCD?I maybe be wrong to that but I recall it was just before the leg connection to case.

 

[Jeff M.]

DO NOT REMOVE EARTH WIRES FROM EQUIPMENT THAT HAS THEM.

You will make the equipment dangerous, and potentially invalidate your home insurance.

I agree 110%.

 

[AnalogSteph]

Talking about earth connections,what's the deal with 60 or 80 Ohm RC circuits coming from PCB (isolated from case) to earth instead of a solid earth connection from PCB to case as usual?

Avoiding nasty surprises with grounded SE gear or balanced gear with Pin 1 Problems would be my guess.