Where in Michigan are u from?
For 4 12s I would do a box around 8 cubes after displacement tuned to 32 hz.u don't have to tune super low to hit the lows. If u tune a lot lower then 32hz ur going to loose output
C-pillar flat wall best score: 158.6db
1 vital power 700.1 @ .33ohm
4 NSV3 18s
8 pwx crescendo 10s
Quad excessive amperage 350alts
4 juicebox 3100s