Subwoofer in the trunk...

[AlterZgo]

For those of you who have one, how does it sound with the rear seats upright? Is there sufficient bass to get into the main passenger compartment? Does it sound much louder with one or both rear seats opened?

Not that this would've been a deal breaker, but after I bought my F80, I noticed it did not have a rear arm rest or center pass through that I was hoping I could leave open to allow bass from a trunk mounted subwoofer box through. Also, my kids miss the center arm rest. I guess this was a weight savings measure BMW took specific to the M3.

[Mandi90TT]

Definitely don't need an open pass through to hear trunk bass.

I have the musicarnw.com level 3 full bass upgrade, you can read my review/install of it here

It does sound a little louder with the seats down, but there is more than enough power in the sub and amp to overcome any small loss of sound with the seats up.