OK, I finally got the $600 Yammie at GC to exhibit some note droppng. It was just a gliss up from middle C with flute and strings layered together. After exactly 16 notes a bunch of the lower ones dropped out. When I started with a low E flat and D flat -- held with pedal -- neither of those two dropped out. So it gives precedence to notes separated from others by time and/or pitch and/or harmonics. Not sure which. Didn't think I could stand there forever playing glisses, thinking up tests.
When I switched to piano/strings -- which is what I tried the other day -- polyphony became 32 notes. Which I spose is cause they have a piano/string "voice" in ROM. So it switched to that without informing yours truly. VERY hard to hear anything drop out with piano/strings.
I also learned that Kurzweils generally have four oscillators per voice, and when they say "32 note polyphony" they really mean 192 oscillators max. Kurzweil should make it very clear in all their specs that their polyphony means 2 to 4 times as many voices as a Yammie or Privia. (Roland? Korg?) How many people cept me are crazy enough to dig this out before making a purchase?
So the difference between the home market and the pro/stage market appears to be about 32 notes of polyphony. Plus you get an extra glob of sounds/features for a buck in the home market because they sell so many more home machines, and software and memory are cheap vs. oscillators.
Thanks for your patience. It's all coming together now. I think.
Rick