From digest.v7.n47 Mon Aug 4 22:26:51 1997
From: Aaron Buckley <abuck_at_us.ibm.com>
Date: Mon, 4 Aug 1997 23:11:22 -0400
Subject: Re: E36 Stereo Noise

Austin,

I sounds as if you could have two problems:

1. The easiest way to cut engine noise is grounding everything, head unit included, to a single ground point. Optimally, use a grounding block and get it directly attached to the frame. Use 4 gauge off the frame to the block, and then 8 gauge to each component. One question: how many components do you have? Not speakers: just amps, separate electronic crossovers, equalizers, etc..
   • The higher # of components that require separate power supply wires and grounds, the more you'll battle engine noise. I have two Soundstream amps and a Sony electronic crossover. If I were to add 1 more amp to the equation, I get engine noise. The solution to this is get one 6 way amp. Pioneer, Soundstream, Sony, and many other companies make a modestly priced 6 way amp. This can power a set of front components, rear decks, and bridge the other 2 channels for a subwoofer.
2. The second problem may be where the speaker wires and patch cables are running. All e30 and e36 BMW's run power lines to the battery down the passenger side of the car. A major source of engine noise having rca's and speaker wire running down this side of the car. Make sure they're on the driver's side. If not, this is the problem.

I hope this gets you going towards engine free sound. The defroster problem tells me that you probably don't have the head unit grounded with everything else. Post any results or problems, or e-mail me personally if you have any questions.

Aaron Buckley
BCCA Membership # 139801
Federated Systems Group

919-543-9806