I read the primer (Accuracy & Calibration) and it said that it might be a good idea to turn off all treble and bass boosts/cutting. Am I right to assume that the 'Loudness' control on my receiver is a booster? Should I turn it off when I calibrate? I believe it only adds enhancement to the main left and right speakers. That would obviously throw off the surround field in a movie since the center speaker wouldn't have the same tonal balance as the mains. Especially since my front three are timbre matched. I was thinking of just turning the loudness on when listening to music. Opinions?