one way to tell if you elecrtical system is running low on juice is to...turn on your headlights, heater, and just about max volume on the deck. if the headlights or the interior dash lights blinkwith the bass....then you should think about investing in a cap.

yea the standard is 1 farad per 1000wattss.

600x2? what amp is that? what fuse is on the amp? i like to run 4guage to be safe. bump your system for about 15 mins, if the power wire is warm, you might want to get a thicker cable.