I have been considering purchasing a cargo mat for my Passport but am concerned that I may lose some of the base from the sub woofer because of adding another layer of plastic on top of it, what do you guys think?
I don't think that will make a huge difference, expect for maybe some added vibrations. You should be able to optimize the bass and treble settings with some tuning.
Oh, back behind the second recessed area(?) I think I see it. Actually by plan is to leave my seats folded down all the time, they may increase the bass a little as it does not get blocked by the seat backs...