I got a custom box made for my Evo Ix
No. When you get a bag of stuffing (I think they come in 20oz, 1 1/4 lb, bags) take about a 3rd of that bag and stuff it into each side of the box. You won't have any troubles getting the woofers back in. Once you get the stuff and do it, if you in fact do, you'll see what I'm talking about.
I have a 12'' Infinity Kappa perfect.. It sounds great for one sub, not really loud loud, but its defintitly very accurate... Overall a great sounding subwoffer with all type of music... I have a JL 500/1 powering it.



