Modulation effect

The family of effects that vary the pitch, phase or amplitude of a signal over time, including chorus, flanger, phaser and tremolo.

Modulation effects all share an internal low-frequency oscillator that changes some property of the signal cyclically, and what differs between them is which property is being changed. Chorus and flanger delay the signal and vary the delay time, which shifts pitch; a phaser varies phase instead, and tremolo varies amplitude. Understanding the shared mechanism makes the whole family much easier to use, because the rate and depth controls behave in comparable ways across all of them.

Example: A pedalboard section containing chorus, phaser and tremolo pedals grouped together is the modulation section.

Modulation effect

See also