Hey, I own to 15'' solobaric L7's. Right now I am running each in a ported box about 4.3 ft^3 each. I am not sure of what the tuning is because I did not make these box the guy i bought the subs from did. Anyways I'm wanting to run in some spl competitions this summer and need to build a new box for my subs. What should the tuning be for a daily driver but still hit some good db numbers. I was thinking around 40hz but not to sure.