ur kinda off. caps do help. saying all caps are the same is just plain retarded. lets take a pyramid 1 farad cap vs a phoenix gold 1 farad cap. the pyramid cap 1 farad probably covers 200 watts. the pg cap = 1000 watts.

i got 800 watts in my car right now at 2ohms. my car dimmed a bit. i dropped in a yellow top optima and fixed the problem. i still got my stock del sol alternator and not gonna upgrade it til i get another sub. i think all u need is a deep cycle battery and ur set. get a cap. alternators are nice but i'd rather have the battery.