I assume you have these?
If so, that is 1200watts PEAK that those speakers can handle, meaning they are already getting enough power as it is, if those numbers are accurate. And for the $$$, those must be junk man. Why do you think you need more power? Are they not loud enough? lol
I always tell my friends to just get a good quality single 10" or 12" sub in a single sealed enclosure, no bandpass boxes or anything like that. Those, at least to me, sound the best and hit more than hard enough.

I always tell my friends to just get a good quality single 10" or 12" sub in a single sealed enclosure, no bandpass boxes or anything like that. Those, at least to me, sound the best and hit more than hard enough.