[joeykayo]

I know this is kind of an old thread but just wanted to share my settings and methodology.

I used a UMIK-1 calibrated microphone and used REW to do the measurements. I did a few sweep tests with the settings on the car set to 0 and Logic7 turned off. I then used the AutoEQ function in REW to create a correction profile. I then applied that to a MiniDSP (basically a mini computer that does digital signal processing.)

One difference between my settings and Lincoln30's is that I created a correction profile set to a "house curve", specifically the Harman curve. Double-blind tests by Harman and B&K have shown that (some/many/most?) people prefer a slightly increased bass response and a slight treble roll-off as opposed to a completely flat response. If that appeals to you, you may like my settings. I find that flat is not ideal for me especially considering the music has to fight with engine noise, road noise etc. My settings actually weren't too different from the ones Lincoln30 posted as his #2 setting, so that was good. My measurements showed the same issues that Lincoln30 stated were "unfixable" without some hardware upgrades. I completely agree.

After I had the correction profile applied to the MiniDSP, I ran some pink noise through the system and took another measurement and used that as a reference. I set REW to 1/1 Octave because that is all the refinement our BMW's EQ will allow. Then I ran pink noise without any DSP corrections and instead tried to match my reference measurements only using the M3's EQ adjustments.

Here are my settings:
Treble: 0
Bass: 0
Logic7: off
100hz: -2
200hz: -3
500hz: +2
1khz: 0
2khz: 0
5khz: 0
10khz: +1

I've attached my frequency response measurements from REW.

Blue line: EQ settings flat (stock settings) logic7 off
Green line: Correction profile created by REW AutoEQ applied to MiniDSP
Gold line: EQ settings on the car (as closely matched as possible) to REW's AutoEQ settings on MiniDSP

Update: After analyzing the stock settings, it looks like they closely follow the Harman/JBL house curve (it is a Harman Kardon system). It looks like what they've done is boost the lower frequencies (from about 300hz down to 50hz) possibly to account for road and engine noise. Just a thought. These guys might not be so thoughtless after all. I've come to this conclusion because after making the initial adjustments while parked, the system sounded awesome. When I started driving, I felt like the bass was being drowned out by noise. I looked back at the graph to see what I adjustments I should make to the low end. Oh wow, they already thought about that. Darn you BMW! :-)