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Modulation eects overview
Modulation eects—such as chorus, anging, and phasing—are used to add motion and depth
to your sound.
Modulation eects typically delay the incoming signal by a few milliseconds and use an LFO
to modulate the delayed signal. The LFO may also be used to modulate the delay time in
some eects.
A low frequency oscillator (LFO) is similar to the sound-generating oscillators in synthesizers, but
the frequencies generated by an LFO are so low that they can’t be heard and are therefore used
only for modulation purposes. LFO parameters include speed (or frequency) and depth—also
called intensity—controls.
You can also control the ratio between the aected (wet) signal and the original (dry) signal.
Some modulation eects include feedback parameters, which add part of the eect’s output
back into the eect input.
Other modulation eects involve pitch. The most basic type of pitch modulation eect is vibrato,
which uses an LFO to modulate the frequency of the sound. Unlike other pitch modulation
eects, vibrato alters only the delayed signal.
More complex modulation eects, such as Ensemble, mix several delayed signals with the
original signal.
Modulation eects
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