I am actually surprised that the KC 62 did goes flat to 10hz in room! I thought it is severely limited in output down that low, although I myself found the 7040A going down flat to approximately 28hz in room is more than plenty for my taste.After further testing, it turns out it was partially an extension issue. Crossing to the sub at 40Hz with 48db BW obtained almost the same effect on the "punch" as crossing it at 80Hz with mild slope.
FYI, this is the low frequencies with and without KC62, post EQ, in my 45m3 room
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