Change All Selected Notes To A 'Note' is a note with fixed velocity; an 'RNote' is a note with random velocity. All notes have velocities of On and Off, but most MIDI devices ignore the velocity of Note Off messages. Metro interprets RNotes to mean a note of random velocity between the range of the Note On Velocity and the Note Off Velocity of each individual 'RNote' event. With RNotes, Metro literally plays a different velocity (from within the specified RNote range) during every playback pass.