Static Noise

[antcollinet]

Wow, this is a breakthrough!

So, next to me there is also a desktop that I use as my Roon server. I also have a NAS next to it.

BUT, what I noticed is that when I unplug the desktop, the noise goes down by probably 90%. Unplugging the NAS plays no role. So the main issue seems to be with the PC. I can still hear some small static sound btw, but that is when I crank up the volume 100% of the amp, which I guess it is acceptable right? And if I completely disconnect the T26S amp, noise goes almost down to 0.

So what now?

BTW, thank you all for such a great community!

So - physically separate the PC and all its peripherals, and wiring as much as possible from your audio system. Ideally plug it into a separate mains circuit (not just a separate socket, a separate circuit. If you can put it (as a server) in a separate room, do so.

You could also consider earthing the case of the T26S.

Use the shortest possible RCA interconnect. Try a thick (or ideally braided) earth connection between the case of the devices on either end of the RCA cable.

If none of this solves the issue, you might have to bite the bullet and set up for balanced connections between the DAC and both amplifiers.

 

[antanast]

Thanks. Moving the server to a different room will be challenging, but will think of something. To earth the T26S, any suggestions how-to? It already has a three plug connection but maybe it is just like the A11, that it is not earthed.

For the DAC, unfortunately the ADI2 has only one set of balanced connections...

 

[Sokel]

Thanks. Moving the server to a different room will be challenging, but will think of something. To earth the T26S, any suggestions how-to? It already has a three plug connection but maybe it is just like the A11, that it is not earthed.

For the DAC, unfortunately the ADI2 has only one set of balanced connections...

This is a very long shot but worth mentioned every time.
Of all the "if"'s make sure that the PC PSU is properly earthed and bounded to the case.

It's NOT always the case,specially with nice cases,anodized,painted and so.
Sometimes it helps scratching a little the points that PSU mounts to the case.

(I repeat,a long shot! )

Edit:funny story,I once measured 80 Ohm resistance between case - PSU earth pin as if it was an old audiophile pre with the known trick!

 

[Speedskater]

The unit pictured in post #9 has the square within a square safety symbol for a double insulated unit. It doesn't use a Safety Ground/Protective Earth connection.

 

[antanast]

The unit pictured in post #9 has the square within a square safety symbol for a double insulated unit. It doesn't use a Safety Ground/Protective Earth connection.

May I kindly ask you to ellaborate?

 

[antanast]

UPDATE & POTENTIAL SOLUTION: I have used the https://ifi-audio.com/products/gnd-defender/ and since the culprit seems to be coming from a nearby PC (not the one connected to the audio chain), I place the the device on that PC. It has removed probably 95% of the noise. Thinking on whether or not to replace the PSU of that PC.

 

[Speedskater]

They primary function of the Safety Ground/Protective Earth circuit is to trip the circuit breaker if there is a Ground Fault (short circuit) but that won't happen in a double insulated unit.
But what can happen is the units Switch Mode Power Supply can dump noise on to the chassis. Then the only path for the noise back to the AC power system is thru the audio interconnects. So a heavy wire from the units chassis to the chassis of another component (with a 3 wire cord) can reduce this noise.

 

[Speedskater]

Questions:
Does this noise happen 24 by 7?
Have you tried your system in another building?

 

[antanast]

Questions:
Does this noise happen 24 by 7?
Have you tried your system in another building?

I basically used this on the PC and resolved 90 or even 95% of the issue! https://ifi-audio.com/products/gnd-defender/