analog S4

I plan on making a MDF amp rack/shelf that will be mounted underneath the rear deck.

Could I use sheet of copper mounted to the underside of the MDF rack as a ground for the amps?<p>2001 1.8TQMS
Silver, Onyx

Big Stereo Upgrade in the works

siberian

It has to be ultimately grounded to the negative side of the battery.... which is connected to the chassis of the car. You'd still somehow have to tie the copper sheet to the chassis of the car. And, being a sheet running parallel under the amp, that might create some strange magnetic fields which could possibly cause noise in your system. At that point, you might as well do it the tried and true way..... run a ground cable under the back seat and connect it to the chassis thru the seat belt anchor bolt.

analog S4

I didn't think so.<p>2001 1.8TQMS
Silver, Onyx

Big Stereo Upgrade in the works

AndyC

I agree w/ siberian.

D.T.Sealy

I have never checked my A6 Avant manual about this but some cars actually have ideal chassis ground locations detailed in their owner's manuals. If Audi provides this info, it will be of great use to you.