Re: How much amp power needed to drive a 700watt 12" subwoofer?
Those specs suggest that it's a car audio subwoofer. It's might not go loud enough or low enough for HT use.
You could try this alignment - 1.6 cu.ft. tuned to 32 Hz. Assuming that IS a car audio driver with a reasonable linear excursion capability, it should handle 500W quite easily, above 32 Hz of course.