User`s guide

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envelope
A curve that follows some characteristic of a sound. For example, an
amplitude envelope is a curve that follows the contour of a sound’s
amplitude.
envelope follower
A process that “listens” to a sound and tracks its amplitude
envelope. You can use the resulting signal to control various other
effects, such as vibrato rate and depth, so that the effects intensify
as the sound gets louder.
feedback
An effect that occurs when the output of a DSP process is fed back
into the input. Interesting effects can result when you delay a signal,
feed it through a non-linear process such as a filter or power
distortion, and route it back to the input. See “feedback loop.”
feedback loop
The feedback loop is a central principle of cybernetics, from the
flush toilet to the steam engine. Any system that functions by
talking to itself incorporates a feedback loop.
Positive feedback loops result in a snowball effect, with the signal
being re-amplified each time through. Negative feedback loops,
such as thermostats, adjust themselves to achieve a self-regulating
balance.
Multiple signals can modulate each other, resulting in “circular
causality” or “strange loops.” Each signal becomes both cause and
effect. Together, they give rise to a self-organizing system with
emergent properties. See Kevin Kelly’s excellent book, Out of
Control .
See “Ouroborus.”
field
See “value entry field.”
filter
A process that modifies a sound by passing some frequencies more
readily than others, changing the spectral balance of the sound.