Posted this in PSR, adding here for those that use this forum and not the other ...

I did some more "digging" and it appears (from looking at Tyros4 and CVP-609 Data List documents) that the CVP-609 has 96 voices that are not in any current Tyros.

It does appear to be as someone else mentioned - a CVP_609 is really "two sound generators" - one is like a Tyros4 and has 128 voice polyphony and maybe ~1,000 or so voices; the other is the "Natural"! sound generator, with 128 more voices of polyphony, which they use for the Pianos, some E-Pianos, some orchestral instruments, and about 5-6 or so Pipe Organ sounds - none of which seem to be in the Tyros4.

And after playing a CVP-609, I was hoping those sounds would be
in a Tyros 5 - I especially liked the ~5 additional Classical Pipe Organ Natural! voices in the CVP-609 that are unforuntately not in any Tyros. (the Tyros 5 specs did not list Natural! as a voice type).

Jim