Re: **** alternator whine!!!!
Speaker outputs are actually better than preouts in terms of noise susceptability. The audio community says there's more distortion though I've never seen THD numbers to back that up. I'm driving the front stage in my system with speaker level (wiring convenience) and it sounds good to me. And as I mentioned, no ground loops means vey little chance of alt whine.
BTW I used a Radio Shack ground loop isolator on a previous install and the alt whine went away. It was on a sub amp so I didn't care about freq response etc.
1999 Buick Park Ave Ultra
Head Unit: JVC KWHDR720
EQ: Audiocontrol EQL
Front Stage: Hybrid Audio Technologies Imagine 5.25 mids, Morel Maximo tweets
Sub Stage: Boston G3 10", 0.5 cu ft sealed
Amp: PPI Phantom 900.4
Rear Fill: Boston SE953 6X9's