OPERATORS

Question 1

What is an Operator?

Answer 1

An operator is a group of components that interact with each other, making one building block of the FM synthesis setup.

Question 2

How are Operators set up?

Answer 2

Each operator is generally set up the same way, and the arrangement of the operators helps determine the final output of the synthesizer.

Question 3

What is an Operator comprised of?

Answer 3

A basic operator is comprised of the following parts:

• input
• oscillator
• amplifier
• output

Question 4

What is an Input?

Answer 4

An operator’s input feeds into the oscillator’s pitch.

Question 5

What is an Oscillator?

Answer 5

An oscillator generates and outputs a repeating waveform. This waveform will generally have an adjustable frequency / pitch and an adjustable waveshape (e.g. sine, sawtooth, etc.).

Question 6

What is an Amplifier?

Answer 6

The amplifier controls the level of signal coming from the oscillator. An envelope generator can be used to sculpt the level of the signal over time, creating everything from short, percussive sounds to swelling pad sounds.

Question 7

What is the purpose of MODULATORS & CARRIERS?

Answer 7

The output of one operator can be fed into the input of another. This will modulate the pitch of the second operator with the signal output from the first. In the diagram above, we would refer to Operator A as the “modulator” and Operator B as the “carrier”.

Note that we would not be able to hear the output of Operator A in this setup. Its sole purpose is to create a signal to modulate the pitch of Operator B’s oscillator. The final sound that we hear comes from Operator B’s output.

Question 8

What is an Algorithm?

Answer 8

Most FM synthesizers have at least four available operators. While synths may vary in their functionality, most will allow various ways to arrange these operators.

The way that these operators are arranged is called the algorithm. Some have preset algorithms, while others can create custom ones.