60 Cycle Hum from my computer

[rael]

Hi

I have this horrible 60 cycle hum coming out of my computer. I have a 1/8" stereo plug to RCA coming from my sound card into my receiver. I don't get the hum from any other component. Is something not grounded correctly, or is there another cable I can use? It's pretty loud. Thanks.

Jon

[Tony_Montana]

You sound like having a ground loop problem. See if you can plug in your compute [or receiver] to different AC plug, and sometimes rerouting the cable from PC to receiver will help.

If nothing works, then you might need a GROUND LOOP ISOLATOR:

<img src="http://www.partsexpress.com/images/265-012m.jpg">

http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=265-012

[rael]

Thanks, I will try another outlet. Is there any fidelity loss with the ground loop isolator? I mean, does it just eq 60 Hz out of everything?

[Tony_Montana]

Is there any fidelity loss with the ground loop isolator?

The only loss of fidelity you might have would probably be slightly lower volume due to transformer coupling in side the isolator-which you could compensate by raising the volume a bit.


I mean, does it just eq 60 Hz out of everything?

It does not eq 60 Hz out of everything. All it is doing is breaking a "hard" connection between component's ground (via IC shield) which is the main cause of humming.

[rael]

Someone at Radio Shack told me that it wasn't a ground loop, but it was because of the digital output from my cheap sound card. I didn't really think he knew what he was talking about, but the same hum is coming from my Xbox, and it stands to reason that it also has a digital output. So, will a ground loop isolator necessarily solve this? I could find out by buying one for 10 bucks, but I'm cheap and broke and impatient.
:)