I too am very confused about why you would lowpass the underseat woofer at 110 @ 24 when you have a 4" midrange highpassed, per your chart, around 250.
alpina527, I agree that I would not use the amp's lowpass filter in your situation.
@ jml - Per your chart the EP lowpass F3 is around 250. I'm not clear if the blue line is acoustic (with a mike) or electric (how you describe the green line). But given how closely the blue and green lines are mapping each other up to 200 Hz, they have to be the same. These measurements do not resemble the measurements I recall in a 2011 M3 w/EP - I will have to see if I saved the screenshots.
Look, we are using somewhat absolute terms for a relative difference. Many people use the SWS and do not find them lacking. One of the contributing factors is what they listen to. Other folks can't stand their sound, and that too is a factor of what they listen to.
alpina527, what are you listening to?
Musicar Northwest, Portland Oregon
The premier experts on BMW high-performance audio
Home of Tom Miller, 2014 Installer of the Year
Named a Top 12 Retailer in North America
musicarnw.com (please email, don't PM)