Posted by Wayne Parham on April 08, 2002 at 15:42:27

In Reply to: Re: Ground loop and impedance mismatch posted by earwax on April 08, 2002 at 14:18:38:

If there is a ground loop then the only way top solve your problem is to isolate the systems. Generally, the ground must be at the same potential, i.e. very little resistance between all ground reference points, or the two systems should be isolated. Isolation requires something like an opto-isolator or a transformer.

But since your setup is sort of a "get you by for now" solution, it really doesn't merit any real intensive work trying to solve. Put your energies into finding a way to get a better preamp connection method.