did you get to try the first(6dB/octave) and second order(12dB/octave) high pass xover from your sub? how does it sound? :-) From my observation the M2i roll off rather quickly at around 70hz, I think 12dB/octave is a bit too steep for these puppies, 1st order high pass at 80 or 90hz might be ideal the M2i and more than likely would blend better with the sub. Play around with it whenever you have a chance, try to low pass your sub at around 70 to 90 hz and see how it sounds.
By the way, I suspect your M2i sound strained at high volume is more than likely due to underpower, if that is the case then upgrading your M2i to M3/M22 will not help because when you crank it up again it will still sound strained, your receiver is the bottle-neck...not the speaker. :-) perhaps you might want to try getting a higher power receiver or integrated amp, your current HK3270 can be use as a preamp to save some money. Is there anyway you can borrow a higher power receiver or amp from someone and try it out on your M2i?
I'm still taking my time to shop for the right sub, but I wonder what the M22ti sounds like in my living room....hehe.
