You 100% sure you have a good ground? 90% of the time alternator whine is caused by a shitty ground.



some (usually older) pioneers have internal grounding issues. that causes alternator whine when you throw a system in it. if thats your case, and it has been with a few pioneers i've fuxed with, ground the rca shields directly to the chassis of the headunit.

to do that, just loop a wire around the rca shields and put it on one of the screws that goes into the chassis of the headunit. that;s the standard fix for most pioneer headunits.

like this


those damn pioneers will sound great if you just run mids and highs and dont hook them to an amp, but when you hook an amp to them, noise city.

make sure you have good grounds, for the head unit and the amp.

as far as wire routing, i havnt been doing installs that long because i'm only 16 and still in highschool but i honestly believe it makes no difference. i still run them on seperate sides of the car, because it couldnt hurt, but it really doesnt matter in my opinion.

get some good shielded rca's if you havnt already.

ground the rca's to the headunit chassis last, if you try everything and still cant get rid of the whine do that and it should go away.

let me know what you figure out