Amp Picking Up PC Noise - Page 2

Try a different usb port on your computer, is the digital output from you mobo optical or coax?

Optical is immune to computer noise, so that might be worth a try the fiio d3 is a cheap optical and coax dac.

 Are there any problems with the headphones? Have you tried plugging them into different sources and seeing if there's still noise? ( a long shot, I know). The most likely cause is a grounding issue.

 Also, try using the E7 out of a different source.

Quote:

Originally Posted by JRG1990 

Try a different usb port on your computer, is the digital output from you mobo optical or coax?

I glanced at the back of his mobo and he should have both a standard optical Toslink and coax connection on the leftmost side.  I have three computers all with Gigabyte boards from the same generation, have tried both the Toslink and coax, and they both work great.  I prefer the coax.

That's kind of strange that you're hearing the noise as your processing load increases.  From what I've experienced and read, that was more of an issue with older, less powerful computers, though it's still there (which is why some music players put the computer into hibernation mode).

My suggestion would be doing the following two steps:

1) Get a digital signal out of your mobo via Toslink or coax.  Like you've figured out, you'll need a DAC with S/PDIF inputs to do so.

2) Make sure you're outputting WASAPI, not DirectSound.  It's easy to do in Foobar.

Some other things to check in your music software:

- Try turning off equalization (make sure everything is set to 0 in your equalizer)

- Turn off all DSP enhancements

- Turn off Replaygain.  I've noticed noise/distortion listening to classical music at loud volumes with Replaygain.  When I turned off Replaygain, all the distortion went away.

I'd suggest opitcal over coax, coax can still transfer computer noise and optical can't because it's light, so optical alone carrys the signal no noise. coax and optical sound the same I can't tell the difference, I think the cheaper plastic core optical cables the attenuation is a bit high causing it to sound worse than coax, ideally you want a glass core cable so the attenuation is much lower.

Hm, I thought a digital signal wouldn't transfer noise, whether it was Toslink or coax?

I hear a definite difference between the two, as well as all my friends who have A/B tested my system.  The Toslink sounds thinner, less bass impact, but it's a little easier to pick up on details.  The coax is more full, better bass, and seems a bit more musical.  Not a huge difference between the two, though.

Implementation will vary by DAC, but a good 75ohm coax implementation is usually superior from what I've read most audio and home theater people say.

A coax connection it's connected to the dac and computer by a metal to metal connection so noise from the computer can still travel down this connection, it depends how the dac is going to handle the added noise I suppose, a optical connection works by light the signal is trasmitted though the cable as light no noise from the computer get into the signal and none transfered to the dac as theres no metal to metal connection so it's a noiseless signal.

A possible option could be to try an outboard usb to SPDIF converter with toslink, then anything sent from the usb would be turned into spdif outside the computer. Then if you use optical to your your dac there really shouldn't be any inteference allowed from your pc.  

Then your be using 2 clocks and that will increase jitter alot.

Quote:

Originally Posted by Davienr or a mic plugged in or anything simple like that?

Disabling all inputs you don't use might help

It's really any processing activity which is causing the distortion you're hearing.  That's why some of the audiophile music players have a hibernation mode, which does exactly what it sounds like (shutting down and deprioritzing all the non-essential services).  The odd thing is that decent computer components are good at minimizing that interference you're hearing, and your computer doesn't exactly have cheap parts.

Like some people have suggested, a Toslink (optical) connection out of your mobo to a discrete DAC would be the best possibility to first experiment with to solve your problem.