Yes it is a wonderful room with surprisingly good acoustics. Its not exactly without treatments since the wooden slats on the peaked ceiling effectively act as diffusers. I suppose it has a lot to do with the large airy dimensions (40 ft x 20ft x 15ft) and the fact that the speakers are up high pointed down. The 3 vp150s work very well much to my other surprise.
Initially I had thought m3s or m22s but the horizontal mains seemed to work best with the high placement. Also the a-1400-8 really makes them reach their full potential. The black couch is some 20ft away so the more powerful amp really delivers when dynamic range is needed. No audessey equalization necessary with that Onkyo though he is very much against such things anyway.
