This is a long thread so having not read through all pages I don't know if this has been covered before but here goes.
Currently tweaking my Pioneer SC-LX56 as per the guide up front of this thread, with some added extra steps.
Following the first "Full Auto" step, as well as changing the speaker size to small and checking the crossover is at 80Hz, I also use an SPL meter to make sure all the channel levels are equal.
Then I run the "Auto" stage (with "Keep SP System") and proceed from there up to the last stage, run the advanced EQ calibration and then proceed to this next step, not mentioned in the page 1 guide of the thread.
But is mentioned here
The guy there, Ellis DJ, recommends running the Reverb Measurement, with EQ on and then loading the data into the PC MCACC app, checking the "After" graphs for each channel, using that data to help tweak the EQ settings in order to better get a post EQ flat response.
(Tweaking, then rerunning the Reverb measurement to check progress etc)
He does mention there though that the 125HZ range in each channel of the EQ settings should be left alone, no matter how far off it looks in the initial "After" graph. Something to do with the standing wave control being on, and thus the amp integrating this part of the Bass range better than attempting to tweak it in the EQ settings. Would that be right ? (a detailed explanation of why not touching the 125Hz level if that were the case would be appreciated)
Given how far off the 125HZ is from the target level on some of my channels when looking at the initial "After" Reverb measurment (with the front left particularly the 125HZ is 2 to 3dbs higher than everything else.... but my left front speaker is in the most difficult spot of them all I think, given my odd room layout) I am, of course, tempted to tweak that too.
Then once I have run/tweaked the Reverb measurement (EQ On)/EQ settings several times, with the aid of the graphs, in order to get flat across all my speakers, (usually all flat to around the 59DB level), I finish off with resetting channel levels using the SPL meter (and the AVIA disc)