step one.....get new subs.....
they're only okay subs that can only handle 150w if you have the blue ones, and if you have the silver ones, its 175w....
I should know, I've now got the silver ones cuz of warrantee replacement.....
if you guys think that your friend is pounding hard......then you both have never heard a real system....
I had my JBL 1200.1 to both of my old ones after I blew my boston acoustics

, and even on about 1/4 gain, I blew them both by accident....
seriously.....invest in better subs and then do what sman says and sell your 3 amps and buy one good one