I've had great success with the auto set-up from a practical sense. I suppose if I really cared about a decibel or a fraction of one I might think differently. It's been fine for me and I know the distances that the auto set-up sets are accurate.
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Outlaw 990-7500, OPPO BDP-83, Main L&R: B&W DM604s3, Rears: B&W DM602s3, Ctr: B&W LCR600s3, Velodyne SPL1200R, Outlaw, Signal, Blue Jeans Cables, Sony 52W4100 LCD, Harmony One