i am building a new box for my subs but was wonderin if someone could help me with some dimensions... i want a dual ported box where each chamber is about 3 cu ft tuned to around 38-40 hz. The max dimensions I have to work with are 24x36x30. I am goin to be usin 3/4 MDF, sealin it with gorilla glue and that puttin some screws in it. Thanks