I can't explain the polyphony issue any better than it's already been said here.

What I can tell you is that when I had the PSR2000, with 64 notes of polyphony, and played the same pieces on it that I played on my PA80, with 62 notes of polyphony, in comparison, I often noticed dropouts on the 2k but not the PA80.

I often used the exact same styles, as I converted and interchanged my favorites from both boards.

One of my chief complaints with the original Motif classic ( also a Yamaha board with 64 notes of poly ) was a noticeable dropout when I played over sequences. It was more than adequate however, when I played it as a solo instrument.

And yes, I still experience the occasional dropout when playing over a sequence on the ES, and it's 128 notes of polyphony. It isn't nearly as often as when I had the "classic" though. I have rarely had this experience with my PA80 btw.

AJ