I just love breaking the rules. Here is my home sub project built using a car sub (Cerwin Vega V-Max 15). Yes, it's big and yes, it's sealed and yes, it does HT very well. Initially I was going for a ported enclosure but the specs of the driver indicated a sealed box. With an f3 of 25.5 a Qts of .70 and a group delay of around 12 ms, I've got no complaints =) If I can stop playing with it long enough, I'll finish the outside of the cabinet.
what amp are you using to power your sub. in my HT system im using a pyramid 800watt x2 home dj amp and then a couple crossovers to power my speaker line out RCA plug. im using it to power a 15" concept smash series in a bass tube and a 12" infinity kappa perfect in a bass tube ( the 12" started in a down firing sealed box that was built to the subs best performance. the problem was that i heard the support beams under the floor , the floor , walls and everything else rattle to no end. the ported gave me the low audio thump but not the felt rattle that is most common to sealed enclosures. -for home use i do recommend 2 15" woofers because the 12 is way to quiet! a single 15 will sound pretty good but i have tested 2 ported 15s and they are above and beyond. -the system that i added them onto was a bose lifestyle 8. sounds very good.
I've run it with two different power amps. A Yamaha MX-830 with 230 watts RMS per channel into 4-ohms, with 440 watts per ch. dynamic power (DVC sub) and an old Hitachi HMA-7500. The only spec I could find on the 'H' was 100 watts per channel into 8-ohms. Both of these are beasts in every sense. Big bad and weighing in at more than 30-lbs ea. The crossover duties are handeled by the receivers internal crossover.