So, I used some time this weekend to re-calibrate my system using the newly discussed method of letting the AVR figure out delays (distances) for channels that aren't being processed by the 88a.
In my particular case, I wanted to re-run the calibration anyway since I discovered that I had erroneously been running my subs with a lowpass filter in place in the inuke6k. Probably not an issue, but removing one more unnecessary crossover from the chain seems like a good idea.
I'm running 9.1 and using the 88a to correct my front heights instead of my rear surrounds, so getting the delays correct for the rears always involved some guess work.
A few interesting things happened.
1) My Denon x4000 very happily measured the distance of all of the speakers. About 23.3 feet for all dirac channels, and realistic distances for my rear surrounds. However, if I ever go back into the manual settings to check the distances, I now get an error saying that speaker distances are "invalid" and should be re-set. Hitting "back" again does get me out of that screen, without being forced to change the values.
2) Does anyone know how Audyssey (or other systems) figure out "phase"? I found it very interesting that I got an error for phase for *only* my two rear surround channels. The only ones that are not using the 88a. I would have expected it to detect a phase error with the 88a channels, and *not* the rear surround channels. (yes, I'm certain that phase is actually correct). As previously posted, telling Audyssey to "skip error" is a reasonable thing to do here, since you only care about the distances.
3) Nice(?) side effect of doing this is that the AVR *also* tries to correct levels for all of the channels. Some of us (myself included) have complained that the 88a doesn't target 75db reference, but the AVR does its best to achieve that.
In the end, I ended up not having time to tweak my dirac results as I normally do. I just hit "optimize", and then grabbed an REW sweep of L/R/C. It looks damn fine. As good as any of my previous tweaks looked. Not sure why, really. But then I listened. Fantastic. I may just leave it alone and not tweak...but, then again...I'm also tempted to upload it and see if Jerry/Markus might be able to improve it even further. (Thanks for all that you do guys!)
Last edited by KevinG; 11-16-2015 at 04:17 PM.