Originally Posted by pikkashoe
Room diagram as requested. Let me know what you think
Almost 5000 cu-ft with openings to other areas.
If you went with dual subs, where were you thinking of placing the second sub---perhaps to the side of the sofa near the steps?
The choice will come down to two questions:
1)Have you calibrated the system? If so, what would you typically consider *loud* volume levels? -9dB(under reference), -6dB? Other?
2)If you did start with a single XV30, would you eventually consider adding a second for even more output capabilities?
Dual XV15s (separated) will perform very similar to a single corner loaded XV30 in extension, headroom(clean output)and overall sound quality. Either option should offer solid extension down to the 17-19hz range with clean output(at your seating positions) of 115-121dB. Assuming all speakers set to small and you'l run the bass 1-3dB *hot*....i'd say you are fine for master volume levels all the way up to -3dB to 0(full reference). So the only reason I could see considering a second XV30 would be if you wanted to exceed reference levels(perhaps for very short demos?) or to help smooth out the overall level/frequency response across all the seating positions. Also, it never hurts to have a little extra headroom, that way the subwoofer(s) will be able to recreate the most dynamic peaks with more realism.
If there was no/little chance of adding a second XV30 down the road *OR* your master volume levels will rarely exceed say...3-6dB under reference level I would definitely go with the dual XV15s. As mentioned above(and by "Cowboys" a few posts up), extension and headroom will be very close (to the single XV30) and the dual sub system will almost certainly give you better quality bass across your entire sofa(more even output levels and smoother overall frequency response.)
Power Sound Audio