i have a couple questions. first how would a 12" re mx sound in a bandpass? if the sub doesnt favor bp how would a ported enclosure with the port on the back of the enclosure sound? i need to have the port firing into the cabin via a cut through through the back seat arm rest of a 4 door bmw. the guy wants the sound to enter the cabin via the back seat armrest hole so the trunk doesnt sound like hell.
also he says "the bass just stays in the trunk".... thanks for any advice in advance.

quick sketchup. port directly behind sub. i dont like the idea of the sub firing right at the port. im affard the will be phase and loading issues. any in put?

if both wont work, bp or a ported enclosure like the first picture what about putting a board between the rear of the sub and the port. heres a picture