bloke wrote:...people completely accept "equal temperament + stretch" keyboard tuning (which is quite a compromise from individually tuning 3rds, 4ths, 5ths, and 6ths) so maybe (??) I'm wrong.
Several things. One is that the piano is rich in overtones, not all of which are going to fit a given tuning model precisely. Another is that the piano, being a percussion instrument, is more about rhythm and articulation than it is about sustained pitches, at least in the minds of hearers.
Does Autotune establish equal temperament? If so, how do they get those harmonies to line up? (I mean the harmonies that humans are actually singing.)
One person can be out of tune with some model, but few people have those models in their heads with any great accuracy. Two people can be out of tune, and maybe so can three, possibly four. But sections that cluster tightly around a pitch confuse the perceived pitch (and not necessarily in a bad way), given it a "section sound" rather than a "solo sound". That's especially true when the section players are using vibrato, which all string players do.
I was listening to a double-bass concerto last night on the classical radio station. (You know--radio--that magic medium that sends music and other content--wait for it--
through space!)--without using any digital WiFi or LTE or 5G or anything else you have to pay to rent; but I digress.) The intonation was not pretty. But I expect the player was spending alot of time with his left hand about even with his thigh, where the notes are really close together. It sounded like Scotch that's a little too peaty tastes and smells (blame Doc for getting me on a Scotch kick).
I test my own intonation using recordings, not needles. I do really need to incorporate drones into my practice, but I'm afraid of further annoying the property manager, who already lives with my bad tuba playing. But recordings reveal TRVTH too, and even moreso when they are recordings made with others. I listen to the band's recordings with a critical ear. Is my pitch part of the solution or part of the problem? (It's a community band--pitch is always a problem at some level.) Usually, these days, it's part of the solution. I also ask the (professionally trained) trombone player in my quintet to specifically notify me when I present a note to him that he has to do something unusual to tune to, and he has obliged on a few notes that I was still working out on, say, a new tuba. When I play against the tuner, the needle tells one story, but when I play in ensembles, I hear another story, even on recordings.
All my strategies fall into what amateurs do, however, not what aspiring music majors should consider. Or maybe even aspiring amateurs.
Rick "striving for a tune too diffuse to recognize pitch in the first place

" Denney