Am I reading right that the MMM measurement is with no DRC?
Yes.
If so, did you also do an MMM to validate the DRC?
Not yet.
Assuming I'm right about the legend, it seems to me that the native response is much better than the equalized response.
Maybe, but that's where preference comes in. And references to some statistically validated tests of what folks prefer. I tend to prefer other things than what is "preferred" on average.
Your DRC "flat" response reminds me of the ear-bleeding horror that Audyssey's Flat target curve was in my living room: shrieking on top and neutered on the bottom.
I have had no complaints. AcourateDRC is not Audyssey (which I have never, to my knowledge, heard).
A curve that follows the natural upper bass rise and HF absorption-in-air usually sounds more natural.
That's the theory. I find it a bit tubby sounding after a while. It masks the lower bass. My ear gets tired, I go back to flat.
Is that a target curve you arrived at to suit your taste by iterative listening, or is that just the default curve of the program?
My approach is to launch what was recorded into the sweet spot with as little difference as I can muster in a calibrated and measurable sort of way.
Here's corrected in-room RTA vs whatever is raw/uncorrected on the CD, in this case,
Bobby Previte - Music from the Moscow Circus
I reserve the right to change my mind or method at some future date, of course. Right now, I'm pretty happy with what I have going.
My "EQ" currently. Left, Right, and Both.
Yes, it's real flat.