Sorry, I accidentally hit 'submit' on previous post before typing in what was probably the most important line.

You mentioned loose, boomy bass - and what I was trying to say was that the room is likely to be a much bigger contributor to that than the subwoofer... and that's why I'm suggesting getting even crude bass trapping in there as a first step before you do any further experimentation.

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8