My impression is that the only phase correction Audyssey makes is at the crossover between sub and speaker, I could be wrong. Audyssey doesn't expect your placement for 6 speakers but may not care as much as I think it might and might do better than I expect in eq'g generally. Your speaker placement is frankenstein, tho
That is correct, Audyssey does not care if placement is Frankenstein, vampire or zombie..
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It just take the info collected by the mic positions for all the channels and apply filters to correct levels and phase issues created by the speakers/room interaction. Also, it will try to create filters (regardless of level or phase) within the audible range, unless limited by the user (using Editor App only),or the speakers (roll off point). That is
not just at crossover points.
Below is from the fantastic AH interview conducted by Steve Munz,
in case you are interested in reading/re-reading the whole article:
The Audioholics interview Chris Kyriakakis in order to learn the ins and outs of Audyssey's MultEQ room correction / auto-calibration system. Bass management, calibration, EQ and more.
www.audioholics.com
Note that Chris never say anything about limiting correction to crossover points.
"Chris Kyriakakis:
MultEQ is capable of applying correction from 10 Hz to 24 kHz. However, during the measurement process it first determines the roll off points of each speaker and subwoofer, and limits the correction below that point.
Audioholics: What do you feel are the important differentiators between your room correction solution and competitors?
Chris Kyriakakis:
There are three major components which set MultEQ apart from competitors:
- Taking measurements in the time domain to generate impulse responses
- Taking multiple measurements to inform the filters about the spatial variation of the acoustical problems
- Using psychoacoustic criteria and multi-rate signal processing methods to apply the proper filter resolution where it’s needed the most and to optimize processing requirements"
Below is one of my REW plots for the Left+Right channel, Audyssey on vs off, full range/large, subwoofers off.
I also plotted the same for left only and right only. People dialed in their subs manually, might have missed the point that for optimal performance, they need to consider the interaction between the channels as well. That, to me, is why I believe DRC such as XT32, YPAO and Dirac Live etc., are valuable, at least for FR below the room transition frequency point.