Principles of Chorus

Peter 6Sep12:

• Material heres is transferred directly from the old pages in the Manual (now deleted).
• The page title is purely a working-title. I welcome suggestions for a revised title prior to publication.

Bill 10Sep12: My understanding is that some (many?) chorus effect also apply a tiny pitch shift to the delayed/modulated signal as well.

A chorus is a Delay for which the delay time is modulated by a Low Frequency Oscillator (LFO). The most used LFO waveforms are sine and triangle.

Most modern chorus effect unit, be they plugins or hardware based, also spread the effect signal across the stereo field. Sometimes a parameter to control the depth and other behaviors may be encountered.

Some chorus effect also apply a tiny pitch shift to the delayed/modulated signal as well.

The effect can produce interesting sounds, one of which is to produce the illusion of more than one instance of the instrument/vocalist being present. What you get out of this effect, largely depends on your desire to experiment.

Play with the parameters one at a time and experiment.

Common parameters of a Chorus

Delay Time	Parameter Range : 0.0 to xxx.xx milliseconds This is your normal delay parameter.
Modulation Range	Parameter Range : 0-100% or sometimes in milliseconds This determines the maximum amount of modulation applied to the delay time.
Modulation Rate	Parameter Range : 0 - 20 Hz (frequency) Also sometimes referred to as the LFO frequency. Higher frequencies produce extreme effects.