Ground Loop Madness

[AusPro]

Hi Guys, 

 

Latest Update

: The Humming Noise is GONE when I connect the Wiim Ultra phono grounding pin to a phono or turntable !! 

I have been dealing with a ground loop humming noise for a while. I tried most of the possible solutions but had no luck... 

Here is my whole setup, and some results that I have found : 

With Humming Noise:
- as the Diagram. It makes a humming noise once I connect the DAC and Wiim with a USB Cable / Coax cable or touch it by hand. 

Without Humming Noise:

-Replace the Wiim Ultra with my iMac with a ground wire plug.

-Connect Wiim Ultra & DAC with an optical cable. 

It seems like the whole system would need a ground wire on Wiim Ultra for grounding ? or some player with a ground wire plug? 
As the Wiim Ultra only has 2-pin power. 

 

Or any other method that worth a try? 

Cheers. 

Edited January 18 by AusPro

[sir sanders zingmore]

Is there any reason not to simply do this:

1 hour ago, AusPro said:

Connect Wiim Ultra & DAC with an optical cable. 

 

[andyr]

5 minutes ago, sir sanders zingmore said:

Is there any reason not to simply do this:

 

Sounds right, Trev - except that as, according to the diagram ... the Wiim doesn't have an earthed power cord - so it shouldn't introduce an earth loop?

 

But it's an easy experiment.  

 

[rand129678]

2 hours ago, AusPro said:

Or any other method that worth a try? 

 

Add between WiiM and USB DAC (doesn't need an external power supply):

https://www.amazon.com.au/HS02-Performance-Isolator-Compatible-PCM32bit/dp/B0BTZTDVMK/

[AusPro]

1 hour ago, sir sanders zingmore said:

Is there any reason not to simply do this:

 

As the DAC has a upgraded Unison USB card clock that with a better clock management. And yes, it does sounds better with USB connection. 

[sir sanders zingmore]

2 minutes ago, AusPro said:

As the DAC has an upgraded Unison USB card clock that with a better clock management. And yes, it does sounds better with USB connection. 

Aah makes sense

 

[Addicted to music]

14 minutes ago, AusPro said:

As the DAC has a upgraded Unison USB card clock that with a better clock management. And yes, it does sounds better with USB connection. 

 

Have you Try dismantling this upgrade and then try the same USB cable?

[LogicprObe]

 

You need a $1000 USB cable!

 

Clearly..........wiffout doubt!

[bob_m_54]

You could try running a ground lead from the Wiim (banana socket) to one of the devices that has a grounded chassis/case.

[AusPro]

16 minutes ago, Addicted to music said:

 

Have you Try dismantling this upgrade and then try the same USB cable?

Yup, had this issue when I bought the DAC, I thought a USB card upgrade could solve this issue, which is not

[Addicted to music]

The WIIM has its own dac and analog out.   Have you bypassed the Shcitt dac and connected that to the preamp?

 

or try this:

 

12 minutes ago, bob_m_54 said:

You could try running a ground lead from the Wiim (banana socket) to one of the devices that has a grounded chassis/case.

 

Just remember the WIIM also as a ground for turntable at the back, you can try using that.

 

If the WIIM is just purchase seek advise on where you go it from as they may exchange it or you can take your equipment in so they can determined the issue

[AusPro]

1 minute ago, Addicted to music said:

The WIIM has its own dac and analog out.   Have you bypassed the Shcitt dac and connected that to the preamp?

 

or try this:

 

 

Just remember the WIIM also as a ground for turntable at the back, you can try using that.

 

If the WIIM is just purchase seek advise on where you go it from as they may exchange it or you can take your equipment in so they can determined the issue

The phono grounding pin is the first thing I have tried, no luck.

 

When I connect my iMac ( plug with a grounded wire) to the DAC, the humming noise disappear in no time. 

[sir sanders zingmore]

Maybe it won't help at all (I don't really know much about this stuff), but can you run XLR cables in the rest of your signal chain (or even part of it)? For example between your DAC and your pre 

[Addicted to music]

Just now, sir sanders zingmore said:

Maybe it won't help at all (I don't really know much about this stuff), but can you run XLR cables in the rest of your signal chain (or even part of it)? For example between your DAC and your pre 

 

The WIIM isnt XLR supported

[sir sanders zingmore]

1 minute ago, Addicted to music said:

 

The WIIM isnt XLR supported

I know

 

I said the rest of the signal chain

[Addicted to music]

14 minutes ago, AusPro said:

The phono grounding pin is the first thing I have tried, no luck.

 

When I connect my iMac ( plug with a grounded wire) to the DAC, the humming noise disappear in no time. 

 

if the hum intesnify when you touch the WIIM,  you need to try this:

 

36 minutes ago, bob_m_54 said:

You could try running a ground lead from the Wiim (banana socket) to one of the devices that has a grounded chassis/case.

 

[LogicprObe]

 

Good audio has NO humming noise.

 

Guitar amps with such stuff is very annoying.

 

From all I can see here, the 'Ultra' thing seems to have started the rot.

 

Get rid of it!

[AusPro]

Just now, LogicprObe said:

 

Good audio has NO humming noise.

 

Guitar amps with such stuff is very annoying.

 

From all I can see here, the 'Ultra' thing seems to have started the rot.

 

Get rid of it!

Could be the DAC, could be the Wiim ultra. 

 

When I connect the Wiim directly to the pre amp, no humming issue...

 

 

[Addicted to music]

https://www.audiosciencereview.com/forum/index.php?threads/wiim-ultra-streamer-preamp-review.57342/

 

From this there is nothing wrong with the WIIM.  But hes not measured spdif coax out!  That said the possibility of a faulty unit can be a possibility.   You need to try another unit to rule things out.

[LogicprObe]

 

Mate, I feel for you.

I have had the same problems with home audio systems, PA systems and recording studios.

 

You get the hang of finding the thing you plugged in and just getting rid of it (if possible) straight away.

When the show must go on, you have to act accordingly.

 

In your case, you may spend hours or weeks trying for a silent connection..............and I hope that you achieve this...........yet, it may not occur.

[bob_m_54]

16 minutes ago, AusPro said:

Could be the DAC, could be the Wiim ultra. 

 

When I connect the Wiim directly to the pre amp, no humming issue...

 

 

But, you said when you touch the Wiim, when connected by USB or COAX to the DAC, you get a hum. But you don't get the hum when connected by Optical.

 

Do you also get hum if you touch the metal on the DAC, with Wiim connected by optical?

 

Out of interest, which Schitt DAC is it?, does it have a mains connection, or powered by a DC supply wall wart?

Edited January 18 by bob_m_54
spelling

[AusPro]

1 minute ago, bob_m_54 said:

But, you said when you touch the Wiim, when connected by USB or COAX to the DAC, you get a hum. But you don't get the hum when connected by Optical.

 

Do you also get hum if you touch the metal on the DAC, with Wiim connected by opyical?

 

Out of interest, which Schitt DAC is it?, does it have a mains connection, or powered by a DC supply wall wart?

 

When I touch the DAC with other device (tv sound bar) that connected to the same wall outlet with hand, yes , it hums... 

 DAC is a schiit Bifrost gen 1 with upgraded 4490 board and USB board 

[LogicprObe]

 

SOUND BAR!

 

I think I missed that.

[AusPro]

Guys.... Thank you all for every single advise!

 

The Humming Noise is GONE when I connect the Wiim Ultra phono grounding pin to a turntable !! 

 

 

 

[LogicprObe]

 

JESUS CHRIST!!!

 

Now there's a turntable!