"I don't like the muffelled base when its in the passenger compartment over the boom of under the drivers compartment.
Same problem I had when I first fired up my system. I decided against the sub going at the drivers feet for two reasons, long, expensive RCA's, (three amps), and the "pounding" the dash and guages take on some of the ones I've seen. (can't be good for them). Mine is a sealed box by the way, and did not hit well until I opened the observer seat back, allowing the sub to push air. I corrected the problem by trading my glovebox for a sub vent. If you vent the enclosed area it's in, (pasenger compartment) , it won't sound muffled. I'll try and get some pics but I've seen some on here that made custom vents in the seat base as well...