Ground loop problem in aftermarket stereo install, 94 S4

[Huw Powell]

without even thinking about the source of the "static" yet...


>     For the amp, I pulled 12v directly from the battery, and pulled it's
> ground from a tail light ground.

Ground your amp properly first.  You might be able to find a bumper
mounting bolt or something.  A good bolt or big screw into sheet metal
that is scraped bare is good.

> For the head unit, I pulled 12v from a
> wire in the previous harness, and pulled ground from a ground point
> under the dash.

You might want to examine your 12v source carefully, too.  Try to get as
close as you can to the "X" relay (load reduction relay) output as you
can.  Justbecause a wire in the dash is 12v with the key on doesn't mean
it's a nice clean 12 volt source.

>     Does this sound like symptoms of a ground loop?

Not really, but you could have one.

>  How does one correct a ground loop?

The best way is to 1. make sure every component is grounded very well
and to the same point on the chassis; and 2. "directional" line level
interconnects can help (their sheild is only grounded at the preamp
end).

--
Huw Powell

http://www.humanspeakers.com/

http://www.humanthoughts.org/