ok i just bought an alpine type r 10" dual 4 ohm sub, im puting it in my 71 ford ranger pick up, but there is one thing. the box has to b small enough to sit on the seat and have a passanger ride w/ me. i am hoping to be in the low 30's for herts and have as much SPL as i can in that small of an enviroment. i need help with the planing, im thinkin ported but other than that idk. please help.