Soundtrack Pro 3 Effects Reference (en).pdf - Help Library - Apple

Modulation Effects 8
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.
This chapter covers the following:
• Chorus Effect (p. 106)
• Ensemble Effect (p. 106)
• Flanger Effect (p. 108)
• Modulation Delay (p. 108)
• Phaser Effect (p. 110)
• Ringshifter (p. 112)
• Scanner Vibrato (p. 117)
• Tremolo Effect (p. 118)
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