The box is ported due to the sound proofing of the car. Surprisingly not much rattling at all. Tight and clean bass. 10" is perfect, i was on the fence with 2 12" subs. There has been a few occasions where the gas lid has popped open if the volume is up and and it's hitting hard.
BMW 550i F10/Vossen CV3's/H&R Springs/Dinan S2/Eisenmann Race Quad Exhaust/JL Audio