My room is only 2500+ cubic feet and opens into 2 other rooms. I have dual MFW-15s. Two subs might really be the way to go to fill that huge room. One would work but two would give better options to smooth out the sound. Not trying to be a SheepStar here, but did you just hook them up with a Y adapter, or through an EQ, or how did you do it? And what is the placement of these two bad boys?