Tell us a little about your room and your system and we can better steer you in the right direction. Ported boxes and Dayton drivers are great for movies, but you might be better served with a bigger driver ... or two. For precut, GSG is the bomb. If you’re in Southern California they’re a no brainer, and offer great support. For just a little more more effort you can build the box yourself, check out the Marty Subwoofer thread and the VBSS thread. All the measurements, drivers, amps, and amp settings are laid out in easy to follow steps.
SPEAKERS: 3 x DIYSG 1099's LCR; DIYSG HTM 6's and 8's surround; 4 x RSL C34E's atmos.
SUBS: 4 x UM18-22 Mini Marty's (and always building, currently working on VBSS's).
SIGNAL CHAIN: Denon X4400; Minidsp 2x4 HD; 2 x Jensen Iso Sub 2RX; 2 x NX6000d.