[Schonen]

Use external USB soundcard like EMU 0404 USB to solve the issue. 

 

[Schonen]

Also use optical connection and not coax  from computer audio to EMU if you want to isolate from computer EMI even further. Probably not necessary though.

 

[stv014]

Since the problem is a ground loop, and not EMI, USB will only fix it with an isolator, and optical S/PDIF is definitely preferred over coaxial. As already mentioned, there must be at most one ground connection between the PC and the amplifier, either through the AC power cords (and using optical S/PDIF or USB with galvanic isolation, or an audio transformer), or through the audio interconnects (with a non-grounded amplifier, or other means of breaking the AC ground connection), but not both.

 

[cdq109]

I've run into this problem quite a bit. First on my home PC when I went to hook up my PC to my home stereo. Horrible noise from EMI, impedance mismatch, and ground loops. I saw this item http://www.dak.com/Reviews/2045Story.cfm and was skeptical. Upon getting it (was like $15 back then I think), and upon receiving it I thought it looked like absolute trash and thought this piece of junk could not work. I was SOOOO wrong. All that noise, GONE, instantly. Worked like a dream. Have been running on one of these for like 5 years now. At my church we have a number of PC's hooked up to a rather nice sound system. The house audio amplifiers put out something like 12,500 watts total output, and the system sounds quite good. The same basic problem occurred, horrible sounding audio, and constant hum/buzz/pops. Just miserable sounding. I mentioned these things, we ordered them, now for like double the price, and voila. Totally worth the $30. Our one PC used for sermon audio recording actually has a nice stand alone sound card in it. It did not matter (though I guess that was for audio input). Anyway if you are not looking for idealistic audiophile solution to make your sound perfect, I betcha the above device would work. Now with my stereo system on at about 50% volume and hooked up to my PC's motherboard audio output, there is no detectable "noise" difference than when I have the Stereo in CD mode and the volume at the level with the CD stopped. So all the noise that is noticeable now is inherent to my stereo. 

 

[Schonen]

Yea, ground loop isolators, I have a few of those but have only needed them when using analog connections from PC to stereo. You can buy them at Radioshack im the USA and The Source in Canada. I have one for my car too that is made by Belkin that I found at Walmart.

 

[U2Edge]

I've run into this problem quite a bit. First on my home PC when I went to hook up my PC to my home stereo. Horrible noise from EMI, impedance mismatch, and ground loops. I saw this item http://www.dak.com/Reviews/2045Story.cfm and was skeptical. Upon getting it (was like $15 back then I think), and upon receiving it I thought it looked like absolute trash and thought this piece of junk could not work. I was SOOOO wrong. All that noise, GONE, instantly. Worked like a dream. Have been running on one of these for like 5 years now. At my church we have a number of PC's hooked up to a rather nice sound system. The house audio amplifiers put out something like 12,500 watts total output, and the system sounds quite good. The same basic problem occurred, horrible sounding audio, and constant hum/buzz/pops. Just miserable sounding. I mentioned these things, we ordered them, now for like double the price, and voila. Totally worth the $30. Our one PC used for sermon audio recording actually has a nice stand alone sound card in it. It did not matter (though I guess that was for audio input). Anyway if you are not looking for idealistic audiophile solution to make your sound perfect, I betcha the above device would work. Now with my stereo system on at about 50% volume and hooked up to my PC's motherboard audio output, there is no detectable "noise" difference than when I have the Stereo in CD mode and the volume at the level with the CD stopped. So all the noise that is noticeable now is inherent to my stereo.

Not to dig up a hella old thread, but I’m having an issue with a Feliks Audio Echo tube amp I just got. Even with no signal cables connected to the back, I get interference to my headphones. It does it anywhere on the same circuit with my computer. If I move it to my kitchen and plug in there, no noise / interference.

The URL you posted no longer goes to a product... do you happen to have a model number? Or any updates or recommendations on fixing my issue? Some people are recommending a ground plug / 3 pin down to 2 pin cheater adapter.

 

[redrol]

I actually suffered from this for YEARS.

Solution. Break the ground pin off your studio monitors power cable (the 3 prong).. OR break off ground pin on the computer power supply power cable.. OR on your DAC/amp. I'd try the speaker ground cables first. Sounds insane I know, but for me it worked instantly and no ill effects now for a couple years.

 

[U2Edge]

I actually suffered from this for YEARS.

Solution. Break the ground pin off your studio monitors power cable (the 3 prong).. OR break off ground pin on the computer power supply power cable.. OR on your DAC/amp. I'd try the speaker ground cables first. Sounds insane I know, but for me it worked instantly and no ill effects now for a couple years.

Thanks for this. I found a 3 prong to 2 prong adapter last night. Tried it. It didn't solve it. Turns out, it wasn't a ground loop interference. It had something to do with WiFi interference. I powered my computer down. Interference was still present. Powered my phone down. Same thing. Powered my router down. Dropped to NOTHING.

Powered the computer back up. Still dead silence. Moved the router that sits on top of my desk further back about six inches. Powered it back up. Little to no noise. Put it on the shelf above my computer next to my Amazon Echo Show device. Noise jumped back up a bit. Pulled the Amazon device away... noise was reduced. Powered the Echo down. Gone again. So I just relocated my Echo to the left side of my desk. Haven't had an issue since. The final layout / setup attached. You'll see how the router is set back on my desk (probably good that I'm not inches from an AX wireless router for 8+ hours a day anyway) and how the Amazon Echo Show is the opposite site of my desk compared to the Feliks Audio Echo tube amp.

 

[redrol]

Crazy man. My wifi router is no where near my main PC.. I run ethernet only. Also Wifi itself generates crazy noise. My audio PC has zero wifi installed as a result.

 

[U2Edge]

Crazy man. My wifi router is no where near my main PC.. I run ethernet only. Also Wifi itself generates crazy noise. My audio PC has zero wifi installed as a result.

My PC is Ethernet as well. I just chose the top shelf as a central location for one of our two mesh routers. I have a MoCA adapter in the office and I wanted the backhaul to the unit to be fast.

 

[Cho Worsh]

For a long time now I have been trying to cure the buzzing that occurs at medium-to-high volume when the amplifier is connected to my PC. This is not a hum that sounds like the typical ground loop at either 50hz or 60hz. This is an electric hissing noise with occasional clicks, and a high pitch buzz whenever I move around the mouse on the desktop. The most terrible noise comes when I launch a 3D application, such as a game. Then a loud hum appears which is very audible even when the volume knob on the amp is turned to zero; this noise only occurs when the GPU is stressed, though I can't tell if the interference radiates from the graphics card or the power supply - or both. I highly doubt it is due to the PSU since it is of high quality and power: Corsair HX1000W...

In any case, I was wondering if any of you have any ideas of how to remedy this issue. Thus far I have done the following to try and resolve the problem (mostly treating this as a ground loop):

DID NOT WORK
1. Connect all devices to the same power outlet
2. Tried higher quality + double shielded RCA interconnect from Supra, which should enhance immunity to electro-magnetic interference.
3. Muted all unused channels for the mic input (NOTE: before I started using a USB mic, I had the same irritating sound whenever I used my analog mic)
4. Chassis grounding (though I'm speculating I made errors in this part)
5. Connecting all devices to the same high quality power strip with transient filter through an ungrounded power outlet.
6. Disconnect one device at the time, in this case PC and monitor. Monitor does nothing. Disconnecting PC while turned off and RCA connected to the RCA out on sound card removes the hum (when volume on max). As soon as the PC is connected again the hum resumes, and becomes louder when PC is turned on. Same happens when connecting RCA to 3.5mm jack on mobo (onboard device). Also tried this on another PC where the buzz became significantly worse. BUT! The same thing happens with the same noise, and buzz under GPU load, when the amp is connected to the monitor (my monitor has a headphone jack + 2x USB ports).
7. (This step is mostly here to confirm it being a ground loop issue and not a faulty amp or an interference issue) While the amp is powered on for a while and connected to the PC, listen intently to the buzz/hum (very audible when GPU is stressed) and then disconnect the power cable to the amp. The amp will still be on and process sound/music until its power supply capacitors run out. All buzz instantly stopped, which confirms the ground loop occuring when more than two power connects are made to the sound system.
8. A medical grade A/C isolation transformer is generally known to be an effective way to obtain galvanic isolation/separation, but it did not work in my case.

WORKED
9. Tried medium priced ground loop isolator at circa $60. This worked in eliminating the ground loop buzz but perhaps at the cost of some frequencies; which is something I want to avoid. Even the more pricey option with Jensen and Lundahl transformers will degrade the audio quality to some extent, though significantly less than a cheap transformer.
10. Another thing that worked was connecting an external DAC via optical S/PDIF. Optical is generally considered the best alternative to avoid noise from interference. Haven't tried Coaxial RCA yet.

Will a better brand/quality of RCA interconnects help prevent the amp from picking up the noise of the computer? I had planned to upgrade my current cables for the Signal Cable Analog II for better shielding and overall quality.

I also tried a fairly cheap ground loop isolator-transformator which eliminated every interference noise coming from my PC and left me with a slight white noise on maximum volume only (but at the cost of some frequencies, I fear; though not that audible.) I have considered buying the Jensen CI-2RR which is a renowned transformator of high quality which should not degrade the audio signal as other cheaper devices do. I understand computers are very noisy environments and not ideal for audio in the first place, but since I am no longer using an external D/A I have to rely on my internal sound card which I so much adore. There got to be something beside an expensive transformator that can fix this.

Please help!

I spent much time and effort before I finally eliminated all noise when using my all tube headphone amp with EL84, 6922 and 274B tubes with the Jensen Iso-Max CI-2RR .

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