128+128 Polyphony

[jimbuist]

Does anyone know specifically what is meant by "128+128" Polyphony in the CVP 307/309 instruments? I have an educated guess, but I'd like an accuarate/official/real answer if anyone knows.

Jim
looking to buy a CVP 307

[kesi]

Hi Jim,

Not quite sure. I can say this however. I went to the music store today and played both the 305 and 307.

The 307 has a significantly richer and more fully "bodied" sound. I am not sure it justifies the cost differential to the 305 but for me it clinched the deal.

[dancaputi]

Ok Jim, I give up. What's your guess? Mine is that they're similar in design to the 200 series having a separate sound generator for Natural! voices. Based on that assumption, one could guess 128 for Natural! voices and another 128 for all the others (including Mega voices and XG). It's funny that it's not explained anywhere. I suppose saying "128+128" is not as misleading as if they said "256-note" polyphony (but it sure leaves you wondering :confused: ).

- Dan C.

[jimbuist]

Well, my guess is that it has 128 Polyphony for specific parts, such as Right 1 & right 2, and 128 Polyphony for other parts such as Left, Accompaniment, Rhythm, etc. Of course, this is only a guess. Now I'm guessing that I should write directly to Yamaha to see if I can get an official answer!

Jim

[ericho]

hi

I found this explanation on a uk site:


The instrument boasts a huge polyphony, which is described as 128+128. Put simply, there is 128-note polyphony for the voices and a FURTHER 128 note polyphony for any accompaniment features being used. This ensures that you will never run out of notes even in the most demanding of arrangements created with the built-in 16-track sequencer.

I'm even more cofused now???

Eric

[jimbuist]

Well, the way I read that, it sounds like I was on the right track. Since my last posting, I sent an e-mail directly to Yamaha. I'll let you all know what they have to say when I get a reply from them.

Jim

[jimbuist]

Yamaha responded to me very quickly regarding the polyphony issue. The response is as follows:

"There are 2 separate tone generators that don't share polyphony with
one another.The benefit is that a thick keyboard performance using
Natural (stereo) piano layered with Natural (stereo) strings would not
"steal" notes from the auto-accompaniment."

Thanks for everybody's thoughts on this. It looks like this is another example of Yamaha really thinking when they built this instrument. They did well!

Jim

[dancaputi]

I had to go back to my 207 manual and find where I read about the 2 sound sources. Here it is:

Built into the CVP-209/207 are two different tone generation sources, Natural and XG. The Natural tone generation source and its voices feature a huge amount of wave memory, giving you enormous and finely detailed expressive power over the sound.
The XG source (which powers the Regular voices) provide maximum compatibility with a wide variety of devices and song data.

And here's the part about how the polyphony is divided:

The maximum amount of polyphony for each tone generation source is set up to best enhance your performance. In general, the songs and styles are played back using the XG source, while the Natural voices are played from the keyboard — allowing you to play the Natural voices with full polyphony, even if the song and style data exceeds the polyphonic limit.

The one thing it doesn't say is - what are the numbers? The specs on the 207 say it has 192 total poyphony. So is that 128 Natural and 64 XG or visa-versa? I assume the 209 having 256 total is an even split of 128+128.

- Dan C.

[jimbuist]

That's good info on the 207/209 series, but I get the impression from Yamaha's response to me that this may not be how the 307/309 is set up. Either way, though, we know that the polyphony is split up and, with 256 total, I'd find it hard to believe that one would run out of notes at all! Thanks for all the responses.

Jim

[dbjorck]

Hi!

I did read somewhere before that the one generator was for Natural voices and the other for the rest. In the same place (I think it was the manual for the 309?) it also said that that is the reason why Revoicing and Accompaniments by default don't use Natural voices, as they assume you would be playing natural voices on the keyboard.

I took one of the preset songs and changed all of the voices to Natural, and indeed I got polyphony choking up in one bar, which it didn't before.

Brgds

Danny