Since my impressions with music(portions of The Planets)were as given in my previous reply here, I decided to check frequencies more precisely, by using a test-tone disc rather than music. First, the very sharp cutoff above 100Hz, regardless of whether the sub crossover was set to bypass(which ordinarily on a sub would permit frequencies above 100Hz to be heard), was confirmed as being present(this was with the receiver crossover set to 200Hz, so as to not affect the result).
Then, with my usual 80Hz crossover set on the receiver(with the M22s set "Small", of course)the difference between the bypass setting and setting the crossover on the sub itself to 80Hz was that an 89Hz tone, for example, was significantly weaker with the 80Hz setting. This was as expected, since the combination of the 80Hz rolloff done on the sub by the receiver(24dB/octave)and the sharper cut made by the sub itself made the net M22/EP500 response weaker in that area than it was with the receiver crossover alone in effect.
So, as was said before, I didn't observe any benefit from the sharper sub cutoff. I'd imagine that if there was a room resonance in the 90Hz area that the weaker sub response would aggravate it less.
