Well i had my single CVX in a 2.0cubic foot ported box tuned to 38hz i think that box was, and was doing just over a 140db at the headrest, with a sony GTR-900D, 912wrms!! So it should do ok in what your talking about!!! But its sealed so im not sure, i would go ported and around 2.0cubes for a single 12" CVX