You don't want muffled bass, and that is what you are going to get with all that sound proofing in the trunk. The hole is not cut out, but its easy to cut. If you are leasing the car you have to go with that I setup for ROBERT-NJ which is a freeair setup similiar to the M5. Just remove the back seat, you will see a rectangular area, cut it out with a rotozip/dremel tool/cutting wheel