i think you guys are delving into too technical terms as to what makes a subwoofer a good one. the understanding of everything is nice, but how important it is matters most.

for diy, i think you can get a better sub than what unferth has for $900. not that his isnt nice or good or whatever, but 500wts rms is not enough for my tastes. components for subs are WAY overpriced though. i guess a lot of technology is proprietary though, and that is why it costs so much for someone to buy and why a lot of companies design parts in house.

i hope this market changes in the future, because i would like to have in wall subs when i get space for a nice theater room. its gonna be hard to part with the ones i have now, but i really like the idea of having it buried in the wall. id do four, one in each corner...