I just built an new box for my subs. I have 2 JL 12w6v2's in a sealed box built to JL's specs...well at least I tried. I have perfect bass drum reproduction, but I put on "How Low" by Ludacris and found I lost a lot of depth in the music; I can't hit those low notes. Is this something I'll have to deal with since I'm now sealed rather than ported? Also, I have a single chamber...I did not split the box. Could that have something to do with it? This is my first ever home built sub box. Is it possible I miscalculated and need to polyfill the box? Otherwise, it sounds great...especially given the materials I had to work with, but I just feel like it is lacking. Any thoughts? Thanks in advance.