The room is 13.5 x 14 with 8 foot ceilings.
That's the total size of the room and everything that it's open to? Because 1500cuft is about the size of a medium-small bedroom. If that's the total size then there are a lot of great choices. SVS's PB12-NSD or PC12 NSD, Hsu's ULS-15, eD's A5s-300 or A3-300, or perhaps the upcoming Epik Legend. Any of those (except possibly the A5s-300) should comfortably handle double that cubic footage as long as the windows and doors are closed. In a space that small I'd be looking for a small space saving solution like a front firing sealed sub (Hsu ULS-15 or eD A5s-300) or a cylinder sub. But another consideration is neighbors. I wouldn't want a rear ported or side firing sub sub pounding on a shared wall, and I'd be careful to avoid shared walls and to put a subdude under a down firing sub.
My larger concern with a room that small would be bipolar speakers. I'd ask the Def-Tech experts if they feel you have enough room to let them puppies do their thing. I don't know - that's why I say ask the experts. But I thought you needed 2-3 feet to the back of them and 3 feet on the sides. Again I don't know so ask the experts on here.
