Why's that? Essentially, isn't that what a walled of car is? A box firing forward into the cabin, totally sealed off from the rear?
because you are trying to pressurize a huge ass area with generally 2 12s or 2 15s, which is pretty hard to do, now if there was a loading wall where the rear seats were, it wouldnt be an issue
firing forward sounds better, because of less rattle, but you need something to load off of, i tested this today, and yes, while it sounded cleaner, less rattle, it wasnt as loud as firing off the driver side and sub facing the drivers side...
I had my T2's firing in the cabin walled off and I liked it but it is WAY louder with my new box...if you did something like Thor though you will have different results...