System: (3) SA-8 D4's Phoenix Gold ZX600.2 titanium. (1200W @ 2 Ohm bridged) Looking for help designing the box for these bad boys. I've don't see any information on the Sundown site regarding recommended volumes / port sizes / tuning, so here I am... I've played with WinISD some, and basically decided to tune it somewhere around 33 Hz. For those of you that have these bad boys, what tuning do you run, what volume of box, and how many subs? For my build I'm thinking of going with .6 cubes per sub (chambered box) with a slotted port that is 5" x .75" x 16" (slot port inside dimensions). From what WinISD tells me this should be sufficient to run @ 33 Hz tuning, but I want input from the guys that actually have these. Also can someone tell me how you factor in a slotted port into box volume? Do you just subtract out the wood and count the air space as part of the box volume, or completely subtract out the entire volume of the port? I plan to start building Friday afternoon.