Currently my box is ported for 35hz. I see people porting down to 20 or lower and, if I remember correctly, when Sundownz was testing the SA-8, his box was ported to like 53 or 54 hz. Is there a general rule of thumb, as in if you want lows 30 and below, daily 30-35, and for SPL comps., whatever you decide to setup, be it 40, 50, 54, etc? Thx,