QUOTE (MikeK @ Mar 22 2010, 05:46 AM)

Alright, the quick version: What size hole do i need to cut in the box to fit a 10" sub? I'm guessing 10", but i'd hate to cut a 10" hole and watch the sub fall in. Oh, i don't actually have a sub yet.....
More Questions:
So my car already has 2 12's in the back, which are a decent amount of bass, but what i want to do is add 2 more subs behind the seats purely for depth of sound (these subs don't nead to be "clear"). I can accomplish this with 10's right? If i have to go to 12's i can do it, but space constraints make me think 10's are better.
Any help is much appreciated.
the hole can vary... anywhere from 9 to 9.75". it will never be 10". what subwoofer is it?
as for your second question... i would highly NOT recommend you add more subwoofers in the back. that could get very tricky and could completely ruin the sound. if you are looking for more depth, either change the frequency of the enclosure or get get different subwoofer.
if you want more bass, there are a few things you can do. get a 3-way components for the front, get a mid-rang woofer... or even put a shallow mount IB subwoofer in the door.
what do you have currently as far as a setup? and what kind of box? is it ported, sealed, prefabricated? is it in a trunk or back of a suv? what are thee dimensions of the box? are there speakers in the rear deck (if its a car). if its ported, are the port(s) and woofer on axis... is the subwoofer and port on the same side... what direction is the port and subwoofer firing...
there are a lot of little things you can do that will drasticly(sp?) change the sound.