I would actually try to find an Now Discontinued B&W ASW500,
which I auditioned for a lengthy period of time a few years ago. Next to REL's for music this little 70w Mosfet 10" front firing sub was amazing! The internal amp was made by Rotel for this sub, & was rated down to 32khz on paper. New price was $500 Used today seen anywhere from $190-400.