[SOLVED] Reducing computer RF emissions?

[halfbeing]

The computer that I use for making music has strong RF emissions which are picked up by my guitar and my basses, and which are very noticeable when I am using distortion plugins. The noise is fairly high pitched and stops and starts rapidly and irregularly, and seems to correspond with computer activity. The reason I think that RF emissions are the main problem here is because they end up being picked up by my guitars even when they are plugged into other devices, such as my bass amp, and not this particular computer; because they stop when that computer is turned off; and because they get louder or quieter depending on how close the instruments are to the computer.

Is there a way I can reduce the RF emissions, for instance by creating some sort of Faraday cage? The computer doesn't have wifi or bluetooth, so it has no need to be in radio contact with any other device. The case is a Fractal Design Define R4, which has soundproofed metal panels on all sides except the back, which is mainly metal, and the front, which is mainly plastic.

I actually believe I have multiple noise issues related to multiple devices, so it could be that the unwanted noises from the desktop computer are due to a mixture of RF parasites and a ground loop, but if I can at least reduce the RF part of the problem, that would be a good start.

 

[delaro]

Keep all your instruments and amps on a different circuit from the PC.
Make sure the outlets you are using are properly grounded.
Use a Power conditioner on the Amps like the Furman M-8X2.

 

[halfbeing]

Thanks for the tips.

I won't be using the bass amp and the computer at the same time. Is there any point, in that case, in using a power conditioner? Basically what I have for recording is my computer, a USB audio interface with its own 2-pin power supply, and my guitar/bass, which is plugged into the audio interface and nothing else.

I'm also having trouble understanding why how the devices are wired to each other will make a difference when the unwanted noise is travelling through the air from the computer to the guitars.

 

[delaro]

You're getting noise from two ways really.

1. Fans on a PC or Coil Whine from the PSU under load.
2. Every thing you plug in creates voltage fluctuations such as spikes, transients, and electrical noise. It can be electronic or transformer-based and your amp will pick all that up.

A power conditioner will eliminate entirely everything on the electrical side, the physical side can be eliminated with proper placement of the pc or the use of sound deadening mats or foam.