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How do you fix electrical interference from motherboard?

zermak

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I used RCA to XLR because on the SMSL SP200 review from Amir, he said that XLR input can somehow help fix grounding issues. I also have used RCA input on my SP200 via Setup3 :(
It helps remove ground loops if you have a balanced signal from the begin otherwise it doens't make a difference and sometimes with a bad RCA to XLR cable (with wrong pins) it can cause more troubles.
And well you didn't specify what kind of connections you used in your posts so I gave you an option to try.
What about the option 2? Use and RCA to RCA cable from the Sanskrit and report back.
 
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nhatlam96

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It helps remove ground loops if you have a balanced signal from the begin otherwise it doens't make a difference and sometimes with a bad RCA to XLR cable (with wrong pins) it can cause more troubles.
And well you didn't specify what kind of connections you used in your posts so I gave you an option to try.
What about the option 2? Use and RCA to RCA cable from the Sanskrit and report back.
Sanskrit RCA to RCA SP200 did not work, same electrical noise behaviour :(
 

zermak

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And then there is the ground connector on the main plug....
That's something to look for actually. I have seen some PSU power cables (or similar) without the connections for the ground. And if the laptop doesn't have that issues @nhatlam96 you can definitely check for it and change it.
 
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nhatlam96

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Alright guys I fixed it. Thank you! I replaced my motherboard with a different one with a toslink input. I then connected my motherboard to my audio system via toslink cable, now everything works fine! No strange electrical noises.
 
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dfuller

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USB can and does work fine. Your issue was likely a ground loop - which using balanced connections can deal with (that means XLR to XLR, or if using phone jacks, TRS to TRS). XLR to RCA does not work and does not deal with the problem.
 

joe hues

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I have asrock a320m-hdv r4.0 as my MOBO, i just bought an amp and a nice pair of headphones? should i get a dac too? id really appreciate any and all help!
 

Katji

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The irony is that the forum needs noise filtering.
 
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trl

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Alright guys I fixed it. Thank you! I replaced my motherboard with a different one with a toslink input. I then connected my motherboard to my audio system via optical cable, now everything works fine! never again usb...
That's exactly how I fixed the "electrical" noises from my XBOX while feeding my amp, by swapping copper for optical fiber.

This is usually happening when all the devices from the audio chain has no real ground, all PSU's are isolated. Probably, finding a way to connect at least one of the outer cases to the Earthing might help, but definitely optical link helps.
 
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nhatlam96

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Little update.
My actual setup uses DAC TOSLINK IN and RCA OUT to fix electrical interference.
Can DAC USB IN and XLR OUT also fix eletrical interference?
 

trl

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I) Use USB Isolator ADuM4160: When no audio is played then the noise is inaudible. However, when I play audio, then the treble gets hot & bloated + various clicks & pops.
Do you have a jumper in there to switch between 1.5 Mbps to 12 Mbps, like shown in https://de.muc89.com/isar540 ?

Maybe the bandwidth speed of this device is simply not enough for high resolution audio, this is why Intona products are so much extensive.

My actual setup uses DAC TOSLINK IN and RCA OUT to fix electrical interference.
Can DAC USB IN and XLR OUT also fix eletrical interference?
If you're OK with optical cable and RCA-out, you could leave it like that for now.
From my understanding the noise might come from the USB port of your PC, but of course you could try to borrow XLR cables and give it a try.
 

Wombat

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I bet not many desktop computers are assembled with due consideration to earthing, grounding and wiring type/layout for audio use.

I have one that has all of the wires bundled together in a big knot to shorten/'tidy' them. I don't use it for audio.

It is in the too-hard basket to trace them all without disconnecting and labelling one end and undoing the knot. I could do a continuity test on each wire but would still be inclined to undo the knot and re-route the wires. Can't be bothered.

But, then, I don't use computers for serious audio - too finicky.
 
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trl

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I bet not many desktop computers are assembled with due consideration to earthing, grounding and wiring type/layout for audio use.
Usually the power supply does, and the PSU is connected to the chassis. Also, the motherboard has several locations to connect board's GND to the chassis.

However, lot of noise still gets out of the case and most of the noise comes from the video-card (VRAM snd GPU), RAM and power regulator related coils. Sometimes even moving the mouse causes noises to appear on speakers/headsets, but usually these are gone after disabling or muting the mic/line-input from the onboard soundcard.
 

Wombat

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Usually the power supply does, and the PSU is connected to the chassis. Also, the motherboard has several locations to connect board's GND to the chassis.

However, lot of noise still gets out of the case and most of the noise comes from the video-card (VRAM snd GPU), RAM and power regulator related coils. Sometimes even moving the mouse causes noises to appear on speakers/headsets, but usually these are gone after disabling or muting the mic/line-input from the onboard soundcard.


Just connecting the grounds to the case is not good enough.

Here is a basic article of amplifier grounding. The fundamentals apply to computer builds but with computers requiring even more attention.

Damn instant internet learning.

Time to recognize experts(in depth knowledgeable) again and ignore instperts(quick uptake surface skimmers).
 
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trl

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Can't see any link yet, but AFAIK most amplifier manufacturers are asking for "Chassis Ground" and not for "Earth Ground" to be connected to the outer metallic chassis, while computers require "Earth Ground". However, there are Y-caps between L-PE and N-PE anyway, just in case there is no Earth on the mains outlet, but this is mostly to protect humans from electric shocks, not for EMI leakage.

Nevertheless, most PC noise audible from our speakers are generated inside PC's case and are also "captured" inside as well, this is why I explained above the case of the mouse causing audible noises in the speakers. There are external noises as well, but still PC case acts as a Faraday cage a bit, so I don't think a DAC or an audio amplifier can be influenced by the noise coming via "airwaves" from a nearby PC, at least this never occurred to me.
Damn instant internet learning.
I guess this applies to all here.
 
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nhatlam96

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I fixed my EMI issues by buying a DAC with proper USB implementation. SMSL SU9 or M500 were both silent with USB, no need for XLR cables.
Therefore, the SMSL Sanskrit 10th MK2 is not recommended for USB use.
 

AnalogSteph

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What's obvious right away is that unlike the bus-powered Sanskrit, the SU-9 and M500 have their own mains power supplies (the former being Class I, the latter Class II), and both are expensive enough to potentially include galvanic isolation. So both USB power conditioning and ground loops may potentially have been the issue when using the Sanskrit.
 
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