Seeing that my 18" Q kept up with the Alpha on 2500W (Q had 13-1500)... im going to have to pass... NOT impressed..tried it in 2 boxes... HDC Destroyed ityou can probly find some used alpha 15s for that price.
Get (2) AudioQue Hdc3 15's. I have 2 in a 7.5 cubes enclosure in my trunk. Works great!
although those are some nice subs.. I think im lookin for something that'll get a lil louder...lookin to street beat... I wanna get these doors flexin a lil bit!!...na jk... I really don't care what numbers I can put up, i Just need to get a lil louder than this 18" HDC3 did/ could with the room I have.pair of rd audio alphas would do nicely... your crammed for space though... i would do 3 12s.. 3 ascendant audio chaos 12s would do nicely.. 6 .25 tuned to 35 with 75 in^2 of port area sounds about right..
alright... right now 3 10's or 2 15's are sounding the best (even though 2 15's will be tight...My btl 15 gets loud as piss and still sounds great at the same time in 3cubs @ 33hz. I really feel the 45 degree angled port corners helps significantly improve the sound quality with this woofer (as it would any woofer). I hope you back seats fold down. My 2 door cobalt with one of the seats down off my 2500.1 is doing an easy 143-145db at its peak. Need to get it metered sometime soon.