[urq] Alternator noise to power AMP

[Ben Swann]

After recently wiring in a power amp to the rear speakers for my '83 Ur
Quattro, there is a whine being picked up by the RCA inputs to the amp.  It
is not picked up by the stereo, front speakers, or if rears are wired
directly to the stereo without an amp.

How can I eliminate this or filter it?  I am using high quality RCA cables -
don't know if they are sheilded.

Also, what kind of capaciter would be good to eliminate powere clipping?

Ben