Before and after measurements
Sorry it took so long for me to post these. The "after" response curve is with the Punch controllers higher than I normally listen --- probably 3 dB or so higher than normal.
The factory BMW response curve is with EQ completely flat.
All these measurements were made using a 6-mic array into our multiplexer. Some smart guys a few years ago figured out that this method gives a good representation of what most people can expect to experience in a car. A single mic measurement just measures that point and response measurements will change with change in position of mic. If using a single mic, you can move them about the head-postion and accomplish basically the same as the 6-mic array.