Modulation Effects

Modulation effects are used to add motion and depth to your sound.

Effects such as chorus, flanging, and phasing are known as modulation effects because they modulate the timing of the incoming signal. Typically, the incoming signal is delayed by a few milliseconds and then an LFO is used to modulate either the delay time, the delayed signal, or both.

A low frequency oscillator (LFO) is much like the sound-generating oscillators in synthesizers, but the frequencies generated by an LFO are so low that they can’t be heard. Therefore, they are used only for modulation purposes. LFO parameters include speed (or frequency) and depth—also called intensity—controls.

You can also control the ratio of the affected (wet) signal and the original (dry) signal. Some modulation effects include feedback parameters, which add part of the effect’s output back into the effect input.

Other modulation effects involve pitch. The most basic type of pitch modulation effect is vibrato. It uses an LFO to modulate the frequency of the sound. Unlike other pitch modulation effects, vibrato alters only the delayed signal.

More complex Soundtrack Pro modulation effects, such as Ensemble, mix several delayed signals with the original signal.