Change Velocity dialog allows you to change velocity of all selected notes by a certain value.
The Change Velocity dialog is brought up by selecting the menu item "Edit->Velocity...".
Change velocity by sets the value of the change. Use negative values to decrease velocity.
Notes that would have velocity more than 127 will be cut to 127, notes that would have non-positive velocity will disappear.
OK changes velocity, Cancel closes the dialog without any action, Help opens current help page.