do you have the rear strut bar? are you looking for subs up port up? do you have the back window wiper? *that last one i didnt take into account* subs up port up is the loudest ive seen so far and ive tried subs up port back as well... but you can fit 4 cubes in the back IF you dont have the rear strut bar
the 21s will have more cone area so the 21s, even tho im a HUGE fan of DC, and i think they DCs will get just as loud, and you will push more air with the 4 x 21s
nothing is holding it down LOL it hasnt moved at all since i installed it on dec 8th... and yeah its a big box but its housing 2 15" lvl 4 XLs so i needed a big box
no mine is ported, then again i said it was 8 cubes, i was giving the dimensions of my box but hey ! and ill go snap some pictures of how it is hooked up *the batt
well, i got 2 15s in a 98 integra 2 dr with my subs right behind the front seats and the port facing up towards the rear window, gets really loud im sure you could do that with 4 12s my box is 8 cubes
i dont know if its been said, what subs are you using and what is it going in? have you checked out jacks sleeper yet? he is doing 150+ from 20hz to 50hz *if i remember right...
he has the 2 12s im assuming in the trunk because he cant fit them anywhere else unless hes a ninja.. but yeah he has 2 9500 mtx 12s and the jackhammer, thats not a bad score considering its a jackhammer LOL