I ve been looking at a few sites on how to calculate enclosure size and im still not getting how to factor in sub and port displacement .. For example if i want a box that s 2.5 ^3 tuned to 30 hz net volume , the external volume would obviously have to be much larger and im just really confused on a simple way to figure this out. Just as an example a box 32x14x14 is 3.63 cubic feet (gross) now how would i figure out sub and port displacement for 30 hz with a sub displacement of .14 , any help or links would be cool , thanks