expression

[Andrew Nolan]

I would like to understand how expression is implemented on the WVR - is the CC expression velocity an absolute amount from 0 to 127 like on the noteOn messages or is it a proportion of a previously set amount -if so, set by what? Is it the same as CC volume?

[WVR Audio]

Hi Andrew,

The formula for a samples volume is as follows:
volume = ( channel_volume * channel_expression * channel_pan * velocity ) / ( 127 ^ 3);

Which produces a number from 0..127, as each of those parameters is also 0..127.

Then the master volume is also applied.

[WVR Audio]

To answer your question more clearly, yes, CC Expression is 0..127. Almost all midi values are 7bit, so 0..127. There are a few exceptions like pitchbend, which are double that, but 7bits is the norm.