An interesting thought, My room is very narrow 3 mtrs deep and very wide. 0.5 ratio.
My Rears need to be Neg phase. (As far as I can tell)
My friend Darren has a 596/561 with DSP5000C and M60's with M33's rear. His room is very much deeper and larger. Checking phase revealed Plus all round.
Could the close proximity (In my case) of front to rear speakers have a major bearing on the Phase front to rear?

Cheers, Chris smile

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