[mathowie]

If you don't want to replace everything (I didn't since all the speakers are 2ohms), I added a JL MicroSub CP208LG-W3v3 Dual 8" Subwoofer with a 250w mono amp from Rockford Fosgate to my Ridgeline and it sounds great, and everything fits in the low channel under the seats, with almost no impact on storage.

All in, I think this cost about 1200 total with a remote bass knob under the dash?