I just bought a new 2011 audi a5, with the bang and olufsen sound package. What i was wondering was if it is a better idea to take out the current sub (by the rear window) and replace it with a 10 inch sub like a jl, or just do a trunk setup. The only problem i see with replacing it, is it is not sealed so itd be a free air, does jl even make free airs anymore? The other question is what would be a good sub, i want something powerful (i really like the w7) but i dont want to destroy my new car through the vibrations, especially the trunk. Also, would it overpower the B&O system? The other thing is i want to still have a lot of trunk space, would it be possible to mount a thin line sub in the side, like where the nav electronics are hidden?

Motoman, I have the same car and just put in a JL 12W3-4 with a Alpine MRP-M500 amp. 500 watts RMS mono and clean as hell class-D amp. 10 inch sub seemed to weak for my taste and I can easily control the sub via the regular base control in the MMI. Sounds great and I am completely happy with it. Minimal space required if you go with a nonported sealed enclosure. Amp mounted on the back of the driver side rear seat.