for 2 15's. i'm probably going to redesign it some in the future, but here's what i've done so far. the ported chamber is 2.5 cubes tuned to 32hz. the sealed chamber doesn't matter too much, but it is around .75 cubes. probably buying some cheap MA audio 15's to try it out, then i'll move up to something better later, or scrap it altogether and sell the 15's.