[s-cars] Coupe Quattro Stereo Wiring

[Mark R]

Ben,
With the dual battery plan (as I understand it), there is a
significant assumption that the battery load will be even, and
therefor little current/ voltage potential across the fuse box.  The
presumption is that both batteries are charging and discharging at the
same rate.  This simply won't be the case, especially since the second
battery is charged though the fuse box.  Remember, any battery is a
LOAD on the alternator.  So assuming the second battery will be
directly attached to the fuse box and the amp is wired to the battery,
any recharging as well as the amplifier's needs with the engine
(alternator) running will be a load through the fuse box.  This simply
is asking for trouble.  Acoustically, I'd be surprised if a "ground
loop" (voltage potential) doesn't get caused by the multiple voltage
sources.

The only way I install multiple batteries is with a battery isolator.
Banks of batteries can be directly wired in parallel (to each other).
General practice is single point load attachment per bank.

If I misunderstood, disregard.  Hope I've helped, but I won't respond
further as I'm getting married this weekend and then going sailing in
the BVIs for 2 weeks!  Yay!

Mark