Kurzweil PC2R Musician's Manual page 100

Descriptions of Parameters
Setup Editor Parameters
Here's another example: reversing a linear velocity curve so that it plays loud when you strike
the keys softly, and vice versa. You might think that all you have to do is set Vel Scale to -100%.
when you do that, you find that all the final attack-velocity values are at minimum. When you
set Vel Offset to 127, the velocity curve gets shifted as high as it will go, enabling the negative
scaling to work properly, as shown in the following graph.
127
64
Velocity Curve (Vel Curve)
So far we've been describing the velocity parameters in terms of linear velocity curves—that is,
the final attack-velocity increases at a uniform rate as your keystrike velocity increases so that on
the graph, the velocity curve appears as a straight line. You can use the Vel Curve parameter to
change the shape of the velocity curve, which provides variations in dynamic response.
The setting for Vel Curve in all zones of the default setup is Linear. There are two other values
whose effects are the opposite of each other. Sin+ causes the final attack-velocity value to
increase faster than the linear curve until your keystrike velocity is mƒ, than slower than the
linear curve as keystrike velocity continues to increase (the velocity curve resembles the first
portion of a sine wave, if you're wondering why the value is called Sin+). Cos+ causes the final
attack-velocity value to increase slower than the linear curve until your keystrike velocity is mƒ,
than faster than the linear curve as keystrike velocity continues to increase (resembling the first
portion of a cosine wave).
5-18
0
64
Keystrike Velocity
Velocity Scale: -100%
Velocity Offset: 127
127