Role of sub woofers?

I had begun thinking about changing out the KEF Reference 1s for floor standers, something like Wilson Sophias, Revel Ultima Studios, or the expensive KEF Reference 207/2s. Then I reset the crossover for a pair of Velodyne HGS-15s from 40 Hz to 80 Hz, and the sound stage size, sound stage depth, and sound stage detail improved so strikingly thoughts of changing anything vanished. I did redo the speaker setup extensively, including redoing all the SMS-1 bass manager connections, so I suspect the vast improvement was due to more than just adding 40 Hz to the range covered by the the subs — I must have fixed some previously unknown problem. Anyway, a setup that I thought was best for jazz and baroque now does large orchestrations convincingly with a sense of spaciousness I had previously imagined only floor standers could deliver. One detail I’ve noticed is that the power-on LEDs of the subs that were previously rarely activated are now usually lighted, suggesting the subs are playing a much more active role.

Well about not changing anything: I have a third HGS-15 I might install on the wall opposite the setup for a three sub distribution.

db