Dali Epicon 6 Exceptional!!
They are rated to 32.5hz with VERY high tech woofers. You cut them @70hz?
Thanks. I love the speakers. I know some don't like the voicing (bump up at ~4 kHz), but I'm mostly a relatively low-volume listener. I have a very odd shaped room with many non-parallel walls; not bothering to post because I'm moving to Europe soon and will have a more normal-shaped room. Current room has a few modes (left sub has a deep cut at 68 Hz and a very slight boost at 130 Hz, right sub filter cuts a bunch at 55 Hz and a tiny bit at 350 Hz). But with the subs where they are, I get "glorious bass" in and near my listening position.
I agree the Epicon's bass response is nice. But it still requires a just a little at the bottom end; to me, that little bit contributes to the soundstage. There is no way I could move the DALIs enough to fix their bass interactions with the room without destroying my soundstage. By crossing at 70 Hz I solve two issues: (1) decoupling mains placement from subs placement; and (2) ensuring that both the mains and subs are in a fairly linear portion of their response curves and away from their limits, meaning my active crossover really is pretty symmetrical around the crossover point (something @erik_squires points out as "a cardinal point" in a different response). That still leaves the DALI's "very high tech woofers" to handle 70 Hz - 2250 Hz.
Every room is different, so it is possible that, when I get to my new home, I may be in a position to place the subs more symmetrically with respect to speakers and cross them lower than 70 Hz. As Erik points out, that might allow crossing at a lower frequency. But every room is different, so I'll measure, experiment with various configurations, and listen carefully in the new location. And just in case, I am building an audio conduit to a location that allows flexibility in sub placement, and that location is part of the dedicated audio circuit to help minimize the chance of a ground loop.