if they are the POWER HX2's, then you have a tad too much space inside, my manual says no more, and no less than 1 cubic foot of volume per speaker in a sealed enclosure, a vented enclosure has a wider range because of the tuning frequencies and all.tony8470 said:they are in an MTX box, at the recommended enclosure size (i forgot what size i think 1.25 cf per sub)