Right out of the box, I'm not that impressed with the S950's vocal harmonizer. The S910 had some pretty good presets for my tenor voice.

With the S950 it seems that if you don't like any of the presets you have to be a sound engineer. I cannot figure out all of these parameters.

Also, the S910 had a SpeedyMouse setting that was perfect for a few novelty songs that I used on Halloween or when I played for children. The S950 is missing this.

How can I learn how to control the vocal harmonizer (It's the same as the T4's)?

There is always manual .I still don't know why Yamaha doesn't turn to TC Helicon or Digitech like Korg did.Vocalist on Korg pa3 is way better than anything on Yamaha.

The manual does not explain ANYTHING.

On the other hand, since the S950 has the identical vocalizer that the T4 has, I'm sure that there is information out there. I just need to find out where.

I'm sure that with some work this will be a better harmonizer than the S910, but I would agree that it doesn't come close to a TC Helicon or Digitech. The Harmony M that I had had some great presets right out of the box.

What kind of parameters are on vh2??

Take a look at the Datalist for the keyboard, there is a fair description of each type in there and maybe you can see what the various tweaks do in that.

Bill