Konut:
I believe the crossover is at 2.65khz. I agree the crossover has a lot to do with the quick, dynamic presentation of these speakers, but credit must also go to the cabinet. While it's not as heavy as the Mini's, it's much more inert due to it being HDF (vs. mdf on the Mini) and having a smaller panel size. In terms of the bass, the Mini's do go slightly lower, but in my room the ML1's are flat to 40hz, which is pretty amazing considering their size.
As a former owner of the Mini's and one who was able to hear them side-by-side with the ML1s, I can tell you the sound of the two speakers is more similar than it is different. What sealed the deal for me was the ML1s ability to get closer to how real musicians sound when playing live.
-Mike