Fm Tone Generation; Operators - Yamaha PLG150-DX Owner's Manual

FM Tone Generation

Before actually editing the PLG150-DX voices, let's get an idea of how the FM tone generator works.

Operators

In the PLG150-DX, there are six special devices called "operators" that generate sine waves. A sine
wave is the fundamental wave of a note, with absolutely no overtones or harmonics added. These six
operators are combined in various ways to make up the different voices produced by the PLG150-DX.
The operators can be used to freely change two different aspects of the sound:
(1) The frequency (pitch) of the generated sine wave.
(2) The amplitude (volume or output level) of the generated sine wave.
6
Operator
The frequency of the
sine wave is changed.
This results in the pitch
becoming higher or
lower.
Operator
The amplitude of the
sine wave is changed.
This results in the volume
becoming higher or lower.