John Ashman's recent post:
"Crossovers aren't instantaneous. If my math is right, it would take a 24dB/octave to the a 10dB resonance peak at 8.8kHz to ~1% distortion. Don't know what crossovers they use, but 24dB/octave is uncommonly high and I don't know where their 5" mid or 8" woofer rings. I forget what NHT uses on their metal 6.5", but I do know they cross it over at 850Hz for this very reason, then move frequencies above that to a 2" dome. On Xd, NHT uses a 110dB/octave digital crossover at 2kHz to cut out a 5kHz breakup mode on a 5" magnesium cone. A lot more effective than a passive low slope crossover."
Axiom has a 8" woofer ???