i'm wondering if any of the forums learned members can share other ideas

Plenty:

https://www.avsforum.com/search/7531261/?q=ground+loop+hum&t=post&c[showFilter]=visibleOnly&o=relevance

 

I'd put this on the Lyngdorf FIRST.

 

I'd put this on the Lyngdorf FIRST.
View attachment 3818074

The OP may be in the U.K.

 

OK then, an adapter to eliminate the ground lug would not change the physical make up of the Lyngdorf unit. It would just eliminate the ground temporarily to confirm that is the issue. Your Denon is "floating" the ground, the Lyngdorf is not. All components should be grounded together or not. That would be the first thing I'd look at.

Obtain an adapter that applies to your region that eliminates the ground.

 

Does your PC have a SMPS? They require shielding and make a ton of noise.

 

Does your PC have a SMPS? The require shielding and make a ton of noise.

I haven't a clue tbh, it's a BeQuiet 1000W PSU i have

 

Hello?

 

How is the PC connected? Use optical audio out instead of RCA to eliminate the noise.

 

ok understood, it can't be a device attached to the PC as when i moved it before and reconnected only the power cord + HDMI cable the interference was still present so i'll remove all the other HDMI cables from the AVR and the COAX from the Lyngdorf tomorrow if the IFI defender + RCA isolator don't produce any changes

 

I would still treat everything as suspect. Either disconnect everything and reconnect one at a time until the noise appears, or disconnect one item at a time until the noise disappears. That should reveal the culprit. If not, it could be a mains electrical issue.

 

disconnect everything and reconnect one at a time until the noise appears,

I'd suggest removing all device's connections except speakers, Denon and Lyngdorf. Add devices one at a time and see if/when the hum presents itself and go from there.

 

if i can't find a resolution would a power conditioner do the trick?

 

 

what a nightmare! You'd hope after decades of manufacturers producing this stuff there'd be a simple fix or better yet effective preventative measures embedded in the hardware

 

They cannot electrically test or reproduce each and every connection/device someone uses in any given configuration. Nor do they care. If their device works as designed and conforms to electrical standards, they are done.

If it makes you feel a little better... you're not the first, last nor alone with your experiences.

 

It's just incredibly stressful to deal with when it feels like a guessing game, with all this said, i just disconnected everything on the AVR except the PC HDMI and the eARC connection to the TV and have a demanding game running on the PC and the interference noise is pratically zero now woohoo! I think the culprit is either my UGOOS AM6b+ or the Denon AVS-S HDMI switch that i got the other week but suspect the former

 

Actually..... ignore my comment about it being fixed.....i'd disconnected the RCA connection between the AVR + Amp

 

I think you need to step away and take a break for a few minutes/hours. Frustration doesn't help.

When you return to troubleshoot, do exactly as suggested and disconnect everything except speakers from the Denon and Lyngdorf and add back one device at a time.

 

I did do exactly that and still the problem is there, if I remove the rear channels from the AVR and run a different HDMI lead from the PC to the AVR it helped reduce the noise a bit, all the cables that run from AVR/amp to speaker and from PC to AVR are buried in the walls, I had an electrician do it all about 15 months ago, I'm wondering if something picking up noise from electrical circuit somewhere

 

Actually..... ignore my comment about it being fixed.....i'd disconnected the RCA connection between the AVR + Amp

How is the PC connected? Use optical audio out instead of RCA to eliminate the noise.

You might have missed my comment earlier.

If you can't implement optical out from the PC, you will probably need balanced XLR before the amp.

 

You might have missed my comment earlier.

If you can't implement optical out from the PC, you will probably need balanced XLR before the amp.

It doesn't help as even when i select a different audio output in Windows the buzzing persists, not only that with optical I'd be sacrificing atmos

 

Sounds like your problem is "coil whine" being generated in / by the PC. The 2 keys here are the fact that physically moving the PC reduced the amplitude of the noise and that the volume of the noise depends on the video cards processing load.

Three things to check in the PC: Is the screw holding the video card to the case tight? Are the mounting screws for the power supply tight? Are the screws holding the covers to the PC case tight?

 

Sounds like your problem is "coil whine" being generated in / by the PC. The 2 keys here are the fact that physically moving the PC reduced the amplitude of the noise and that the volume depends on the video cards processing load.

Three things to check in the PC: Is the screw holding the video card to the case tight? Are the mounting screws for the power supply tight? Are the screws holding the covers to the PC case tight?

Everything is secured properly i know because I took the PC semi apart a month or so ago to clean out all the dust properly. The other thing that baffles me is that the audio setup I have at my desk next to the PC (Nord Ncore power amp with Minidsp flex) doesn't exhibit these issues and it's even closer to the GPU!

 

Make that 4 things: Are you sure that the PC power cord's and the outlet's ground connections are correct? If you have an outlet tester, check to make sure you don't have an open ground.

 

Actually..... ignore my comment about it being fixed.....i'd disconnected the RCA connection between the AVR + Amp

It doesn't help as even when i select a different audio output in Windows the buzzing persists, not only that with optical I'd be sacrificing atmos

I assume when you say RCA, you’re referring to a digital coax cable. @Soulburner may have thought you were using an analog RCA cable.

 

I have the AVR connected to the Lyngdorf via the Chord Leyline RCA cables not digital COAX

 

It doesn't help as even when i select a different audio output in Windows the buzzing persists, not only that with optical I'd be sacrificing atmos

It will help because optical will eliminate it. The noise can not travel because there is no metal in the cable.

I understand you want to do Atmos gaming though.

I have the AVR connected to the Lyngdorf via the Chord Leyline RCA cables not digital COAX

Per my prior suggestion, do they make a balanced XLR version? That is your other option to eliminate noise going from the PC to your amps. Otherwise, do you really need the external amp for this application? Is it so you can power 13 channels for 9.1.4?

 

It will help because optical will eliminate it. The noise can not travel because there is no metal in the cable.

I understand you want to do Atmos gaming though.


Per my prior suggestion, do they make a balanced XLR version? That is your other option to eliminate noise going from the PC to your amps. Otherwise, do you really need the external amp for this application? Is it so you can power 13 channels for 9.1.4?

But I would still need the HDMI connected for video so it wouldn't change anything. Yes I'm running 7.2.4 plus music on the denon pales in comparison to the Lyngdorf

 

I think it's clearly the PC causing the issue and am onboard that the Lyngdorf is more susceptible to EMI than the Audiolab I guess the question is, is it the GPU causing the issue or the PSU, if the latter then hopefully the IFI defender can sort it out

 

So does that mean with the PC disconnected and unplugged, you can crank the volume on the AVR and hear no noise?

 

Is your computer in one of those gamer cases with windows and such? Or is it a more traditional case that's metal all around?

Those gamer cases are basically radio transmitters and glass is transparent to radio waves.

If that's the case you probably can try covering the windows with aluminum foil and seeing if it has an effect. You will probably need to screw to ground the foil. If it works you'll need to replace the case with a plain old computer case.

 

It is a fractal design case with a window yes

 

Here's a full fiber HDMI:

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ruipro.store

 

Looks like a winner!

 

Also ground loop hum is at line frequency. You're in a 50hz country so it will be a dull rumble because it'll be 50hz. Removing the subwoofer connection would cut down the noise a lot which can be used to test.

If the noise is at higher frequency (the subwoofer removal didn't cut down the noise) then it's likely EMI.

 

Will the IFI defender help eliminate the EMI? Or should I consider a PC case without a window?

 

Just because it doesn't have the USB power does not mean it isn't full fiber.

Ruipro non-detachable standard hdmi 2.1 certified 48gbps fibre optic version

AFAIK, all "100% pure/full fiber" require power.


If it's this one, it's "hybrid" and has copper.

RUIPRO 8K Fiber Optic HDMI 2.1b Cable 48Gbps 8K60Hz 4K120Hz Dynamic HDR eARC HDCP2.2/2.3 (Crystal 8K Certified Fiber)

RUIPRO 8K HDMI Fiber Optic Ultra Certified Cable HDMI 2.1 48Gbps 8K@60Hz 4K@120Hz Dynamic HDR eARC HDCP2.3

ruipro.store

 

Yea that looks like the one

 

Until the OP performs a proper process of elimination, he won’t know for certain.