The sound is with certain dvds and programs. Most things it's not a problem.
I did a room calculation, way back when I built the room. It's not perfect, but the acoustics are in the high acceptable range. Not up to the THX spec.
I have a 7.1 system using the Audax Home theater kit. I just built more surrounds to get the 7.1 setup.
I have a Pioneer D912 receiver which has auto calibration for speaker distance and loudness, and also size.