@kota1
Thanks!! So no, a switch on the back is not something I can use for the design parameters of a small box. :)
In fact, what got me started was a very large center design from Troels. I looked at it and kept asking myself "why is he using such a large box, and attempting to make this a full-range speaker?"
The same with ATC’s larger center, and Legacy.
Making a smaller, bass limited box is a key design parameter here. Now all of the woofer and amp’s output goes to the 80Hz to 350 Hz range, which is actually serious overkill, but able to match my subwoofer at full output. The normal distortion which would be present below 100 Hz will now vanish.