I read on this site one time, about someone using 4 deathboxes in extended cab truck. The spl was up there, I dont remember how much. My question is....I already have 2 DBs..I would like to do the 4 box setup just for giggles....I have 2 different sets of speakers. Would there be problems using 2 different set of drivers with completly different paramenters? Cancellation or anything like that? I have one set of Audiobahns that are pretty impressive as far as low extension, and a set of MTXs on the lower side of the scale. Would it be better to just do the clamshell thing with 2 boxes? Ideas anyone?  I have a sealed box under the seat now that sounds fairly nice for 10s. I am from the old school days. I dont remember getting the same output from 10s all them years ago.