Very large room HT

It doesn't matter what speaker you use. I would use the PLW-15 Always from 16-140hz. But you need Audyssey pro to use it this far. Without I also could not use it this far. Without Audyssey pro there are different rules. The PLW-15 is without Audyssey Pro a very difficult subwoofer to control. AVground you need to read better, I do not sell Revel speakers. I prefer Pass Labs power amps. I use the Onkyo PR-SC5509 as a Pre-amp with my way of Audyssey Pro measurement. Loudspeakercable; for my front speakers and centre I use Audioquest Redwood 2013 loudspeakercable. For powercables I use Purist Audio. Limited 2013 for poweramps. Interconnects; I use 3 Audioquest Diamond hdmi cables. I use Audioquest Wild Blue Yonder 2013 and Sky XLR. And I use Acapella XLR pure silver interconnect.

Soon I will buy the new pure silver Audioquest Wild dog subwoofer cable with DBS72 when it is available. Pure silver will give you more speed and more details also from 60-140 hz.

"Audyssey pro" takes care of setting. That makes sense!
Thanks for details!

When I compare for example the Onkyo TX-NR5010 between XT32 and Pro the difference is stunning. Like you have a set which is 2-3 times more expensive. The drive and timing is superior. Like you bought a biggerpoweramp. But also the difference in sound is huge. So much warmer and much moe details and air. The stage is wider and deeper as well. The subwoofer is a lot better integrated and has a lot more control and drive as well. I have to tell that I measure at total different hights and places than Audyssey says. There way is ok, but to be honnest by far not good enough what i would want. My way measures a lot more dynamics and details. Also is my way of measurement superior in sharpness of the individual focus of voices and instruments.