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Ground Loop / USB output noise

Smychavo

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I'm hearing ground noise from my PC source. It's a custom tower PC, which through a Apple Type-C to 3.5 mm, connects to a Schiit Asgard 3 which powers my HE-4XX headphones. Noise is source-agnostic, connecting to mobile devices removes the noise completely. While PC headphone out, or USB ports, and by extention, the headphone output of my monitor outputs noise, and sounds like ground hum mixed with computer activity, which changes depending on the current load on my system, like gaming, or even moving a tab around.

I'm contemplating whether to buy balanced amp and DAC, or to try my hand at isolating the usb source, or my pc, though in that I have a few questions:

is it safe for a isolation transformer to be plugged into a power strip?
Schiit's Unison USB supposedly isolates the USB input, would adding the ESS DAC for Asgard 3, or a Modi 3+ solve my issue, or would any other SE DAC offer the same isolation on its USB input?
Lastly, would balanced simply be a better long term solution? If so, I'd rather do that than try to dance around this issue if it's the be-all, end all solution to my problem.

On a different note, I've watched Amirim's video on understanding ground, and on balanced audio, but I'm still unsure of myself as to what is the ideal solution in my scenario.
 

levimax

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Best long term solution is balanced connections. A DAC connected with optical TOSLINK would probably work as well.
 
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Smychavo

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Best long term solution is balanced connections. A DAC connected with optical TOSLINK would probably work as well.
Ah, understood then. Might stick with getting Schiit's balanced offerings then. Judging from the reviews here they seem like a great combination for a semi-low cost with tons of power to boot.
 

Count Arthur

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Which motherboard and PSU do you have in your PC?

Have you, or are you able to try the Type-C to 3.5 mm in an alternative USB socket, or do you have a labtop or another PC you can try?

Some PC power supplies are noisier than others and you may find some of the USB sockets on the same motherboard are better than others. Also try and keep your audio cables separate from mouse and keyboard cables. I had an issue where I would hear a buzzing from my PC speakers when I moved the mouse around, which was solved by keeping the audio cable for the speakers away from the mouse cable.
 
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Smychavo

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Which motherboard and PSU do you have in your PC?

Have you, or are you able to try the Type-C to 3.5 mm in an alternative USB socket, or do you have a labtop or another PC you can try?

Some PC power supplies are noisier than others and you may find some of the USB sockets on the same motherboard are better than others. Also try and keep your audio cables separate from mouse and keyboard cables. I had an issue where I would hear a buzzing from my PC speakers when I moved the mouse around, which was solved by keeping the audio cable for the speakers away from the mouse cable.
EVGA Bronze 500B PSU
MSI B350 PC Mate

All noise and hum goes away connecting it to an external device such as my 2020 Macbook Pro 15" or my iPhone 11 Pro Max. In the Mac's case, the noise is gone regardless of input, be it the 3.5 mm input or Type-C dongle. My cables seem to be just fine, messing with placement does not change the intensity of the noise.
 

BDWoody

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It's a custom tower PC,

Does it have any optical toslink outputs? Sometimes they build them into the audio jack like in the Chromecast Audio... If so, that might be easiest.

I hate grounding issues...they can be such a pain.
 
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Smychavo

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Does it have any optical toslink outputs? Sometimes they build them into the audio jack like in the Chromecast Audio... If so, that might be easiest.

I hate grounding issues...they can be such a pain.
My board did not come with any optical outputs, and I do not have anything that can accept it as an input either, as I do not have a dedicated DAC yet.
It was mentioned earlier in the thread, but it's most likely a better option to swap from SE to Balanced gear as soon as I am able too. In which case, I am in no hurry to do so as I am saving up. I'm looking at Magnius/Modius since I am familiar with Schiit, but if there are better alternatives for power/low noise, I'm open to suggestions.
 

somebodyelse

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You could try an inexpensive USB isolator if you can live with the limitations. They only do 'Full Speed' (12Mbps) not 'Hi-Speed' (480Mbps) which limits DACs to 24/96k stereo, and may cause compatibility problems. I don't remember any reports either way about using them with the Apple dongle so please report back if you try it. Hi-Speed isolators exist, but are significantly more expensive. Also look out for how different isolators deal with power - some use onboard DC-DC convertors to isolate power, which may limit the available current. Others provide a socket so you can connect an external PSU, but that might have ground noise issues of its own.
 
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Smychavo

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You could try an inexpensive USB isolator if you can live with the limitations. They only do 'Full Speed' (12Mbps) not 'Hi-Speed' (480Mbps) which limits DACs to 24/96k stereo, and may cause compatibility problems. I don't remember any reports either way about using them with the Apple dongle so please report back if you try it. Hi-Speed isolators exist, but are significantly more expensive. Also look out for how different isolators deal with power - some use onboard DC-DC convertors to isolate power, which may limit the available current. Others provide a socket so you can connect an external PSU, but that might have ground noise issues of its own.
Would the ifi idefender work in this situation? It's the only isolator I've found that does Type-C to Type-C
 

audio2design

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You could try an inexpensive USB isolator if you can live with the limitations. They only do 'Full Speed' (12Mbps) not 'Hi-Speed' (480Mbps) which limits DACs to 24/96k stereo, and may cause compatibility problems. I don't remember any reports either way about using them with the Apple dongle so please report back if you try it. Hi-Speed isolators exist, but are significantly more expensive. Also look out for how different isolators deal with power - some use onboard DC-DC convertors to isolate power, which may limit the available current. Others provide a socket so you can connect an external PSU, but that might have ground noise issues of its own.

There are high speed models as well now. They are not $29.99, but still not uber expensive, i.e. $200-300.

Just one of many: https://intona.eu/en/products/buy/7054/
 
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Smychavo

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With prices i like that i'd rather just buy the balanced stack and be done with this issue. My goodness those are some pricy bricks
 

JayGilb

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I'm confused about your connection description: " It's a custom tower PC, which through a Apple Type-C to 3.5 mm, connects to a Schiit Asgard 3"
Do you have the additional usb card D/A installed on the back of the Asgard 3 and you're using a usb-c to usb-c cable to connect the PC and Asgard 3 ?
 

somebodyelse

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There are high speed models as well now. They are not $29.99, but still not uber expensive, i.e. $200-300.

Just one of many: https://intona.eu/en/products/buy/7054/
That's what I meant when I said 'significantly more expensive' - it seemed a ridiculous amount to spend compared to the Apple dongle. $15 for something that has a fair chance of working but isn't a certainty seemed much more reasonable.
 

somebodyelse

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I'm confused about your connection description: " It's a custom tower PC, which through a Apple Type-C to 3.5 mm, connects to a Schiit Asgard 3"
Do you have the additional usb card D/A installed on the back of the Asgard 3 and you're using a usb-c to usb-c cable to connect the PC and Asgard 3 ?
I assumed it was an Asgard without a DAC module - the Apple dongle acts as DAC with a mini jack to RCA analog connection to the Asgard.
 

Matias

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somebodyelse

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Would the ifi idefender work in this situation? It's the only isolator I've found that does Type-C to Type-C
Maybe - I don't know exactly what it does, and their tech note is a mixture, of truth, half-truth and audiophile buzzword rubbish that doesn't inspire confidence. On the other hand if you search this site for idefender you will find a fair few people reporting success with it, along with a few failures. I vaguely remember someone posting a schematic showing the sort of creative standards violation that you can often get away with, so long as neither end is too fussy, but won't work with everything. I may be thinking of something else though, and can't find the post.
 

Berwhale

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To solve my ground loop issue (with Topping D50s single ended DAC)...

1. I put a cheap USB isolator between my DAC and PC. Cost about £15 Amazon, this worked fine but limits USB bandwidth and sample rate.

2. I put an SPDIF/TOSLINK adapter plate in my PC (wired to motherboard header) and connected to DAC via TOSLINK. Cost about £12 from Amazon, this also worked fine, but also limits sample rates to those supported by the connection. I also couldn't use the Toppig ASIO driver.

3. Bought a Topping EX5 with balanced output. Cost: A lot more than the above :)

TBH, there were no audible differences between the options above, but I had other reasons to buy an integrated DAC/Amp and replace my separates.
 
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Smychavo

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I'm confused about your connection description: " It's a custom tower PC, which through a Apple Type-C to 3.5 mm, connects to a Schiit Asgard 3"
Do you have the additional usb card D/A installed on the back of the Asgard 3 and you're using a usb-c to usb-c cable to connect the PC and Asgard 3 ?
Ah, yes, the posts further below would be correct. The dongle serves as my DAC for the time being.

Maybe - I don't know exactly what it does, and their tech note is a mixture, of truth, half-truth and audiophile buzzword rubbish that doesn't inspire confidence. On the other hand if you search this site for idefender you will find a fair few people reporting success with it, along with a few failures. I vaguely remember someone posting a schematic showing the sort of creative standards violation that you can often get away with, so long as neither end is too fussy, but won't work with everything. I may be thinking of something else though, and can't find the post.
Call it petty, but I feel more comfortable buying something that would solve the issue with certainty. Least for the time being keeping the volume a bit down recuces the noise, though it's marginally audible. It's annoying, but not end of the world annoying. Least by the time I have balanced gear this'll be an issue of the past.
 

AnalogSteph

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The Asgard 3 is a bit of silly construction, IEC class I device with unbalanced connections only. I guess it still makes sense if you use the optional DAC module. What cans are you running? You may want to consider downgrading to a Magni Heresy / IEMagni, which while a bit less powerful wouldn't have this problem and would save you a chunk of cash to boot. (Solving your problem and actually saving money in the process, how often does that happen?)
 
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Smychavo

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The Asgard 3 is a bit of silly construction, IEC class I device with unbalanced connections only. I guess it still makes sense if you use the optional DAC module. What cans are you running? You may want to consider downgrading to a Magni Heresy / IEMagni, which while a bit less powerful wouldn't have this problem and would save you a chunk of cash to boot. (Solving your problem and actually saving money in the process, how often does that happen?)
Hifiman 4XXs
Honestly wanted to have headroom to try out different, inefficient planars down the line so I wanted to buy an amp that had a fair bit of power to run them without a problem.
 
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