Most people I know that have subs in the back say that they sound better with the seats up, sinc the Sub's are to increases Bass. I havent tried this cause I dont own sub's (yet) but thats just what people have been telling me
well every one that i know that competes their system has either their back seat folded down or taken out. and i can tell it dampens the sound a lot because if i roll my windows down it is a lot louder.
the reason it sounds louder when you role your
windows down is becuase you are alolowing the subs to have more air space. if you want your subs to sound good i would leave the back seat in
they will muffle out any midrange sounds that the crossover didnt block out. and whenever you bumb i would leave the windows down otherwise you build a lot of air pressure inside the ca. if you have a good enough system eventually you are going to either blow your eardrums or your windshield (had that happen to a friend). anyway ifyou dont like my advice good luck with the seats.
ive found the perfect answer for this.. i was wondering it myself because my seats didnt fold down and i like the amount of pressure in the car from the woofers to be higher.. so i left the seat up and got the biggest drill bit i could find and drilled holes in the back panel (your 6x9s rest on this panel) and i also removed that very evil foam from the bottom of that carpeted part of the panel and Boom.. ive just increased the amount of airspace without loosing the pressure in the trunk. another thing is to do is to get some dynamat and layer the front of the trunk so all the sound goes to the front of the car instead of rattling the trunk.
hope it helps.. by the way.. dont worry about the holes, its not noticeable and it doesnt affect the 6x9s.