Tutorials and Topics - Peabody Computer Music

Tutorial 19MIDI Control:SynthesizerThis frequency value is multiplied by the bend factor which was calculated in the mainpatch, and the result is used as the carrier frequency in the simpleFM~ subpatch.The frequency of the note calculated from key number and pitch bend dataVelocity control of amplitude envelopeMIDI note-on velocity is used in this patch, as in most synthesizers, to control theamplitude envelope. The tasks needed to accomplish this are• Separate note-on velocities from note-off velocities.• Map the range of note-on velocities—1 to 127—into an amplitude range from 0 to 1(a non- linear mapping is usually best).• Map note-on velocity to rate of attack and decay of the envelope (in this case).157