The auto calibration seemed to properly set my speakers. The distance was accurate and there was no more than 1 or 2 db difference in the levels. I have PSB Silveri Mains set to large, PSB Minis set to small and a B&W cc6 center set to small. The PSBs are 4 ohm and the cc6 is 8 ohm. My HSU subwoofer is self-powered.

Hope this helps.