How to isolate USB instrument from interference conducted by the USB cable

[sunkai]

Hi there,

I have a Behringer iAxe 393 that I connect to my laptop's USB port for power and communication to the software amplifier.

The issue I have is that the power supply unit and fans in the laptop are creating EMI that is being transmitted down the USB cable and being picked up by the coils in the guitar.

I noticed that gripping the guitar reduces the sound's volume, so I thought it might be a grounding issue, but am unsure.

I have tried a ferrite bead on the cable, but that did not seem to do anything. At the moment I am stuck with a noise gate to eliminate the sound while the guitar is resting. This does not help when the guitar is in use and the nosie gate is open.

Any help would be much appreciated,

Cheers

 

[merlin2069er]

you need a usb isolator...

usb isolator | eBay

 

[JaeK]

Noise is an inherent problem with single-coil pickups.
Single coil - Wikipedia, the free encyclopedia

In terms of single-coil guitars, If it's not an issue when playing, it's not an issue.
Even with double-coil, you wouldn't leave the pickup on without holding the strings, unless you're a big fan of feedback.

 

[mcandmar]

I've used a couple, the circuitsathome version with a linear regular circuit i cooked up, or search for the doodlebug on head-fi for an all in one isolator/linear regular board. Both work equally well.