I am using dual Heresys in an attempt to keep up with the K-horns. Their efficiency appears to be so much greater. On my Denon 3801, I'm running the Horns 6db lower than the Heresys. I'll try it with just one. When compared to the K-horns, the center sound seems restricted, not quite as transparent. I have 22" below my screen, max height, for any center. I am using a 16:9, 113" screen, which takes up most all the wall, limiting my "center" space. Thanks for the reply. MD