M-Audio Wayoutware TimewARP 2600 User Manual page 22

3.5.2 Noise Generators
A device that jiggles at random without ever repeating itself is a noise generator. Waterfalls, steam, wind, fans,
and such things are all noise generators.
The spectrum of a noise signal is a statistical distribution of frequency components. (This is the opposite of a sine
wave, which is exactly one frequency.) A noise spectrum that is perfectly balanced throughout the musical range
is called pink noise. Pink noise is very useful in listening tests of loudspeakers, because a trained human listener
can hear even tiny differences between two different noise spectra.
Filtering and equalization can shape a noise spectrum into almost any sound.
3.5.3 Envelope Generators
A device whose output is intended to control some time-varying attribute of an event is called an envelope
generator. These are sometimes referred to as transient generators, to call attention to the fact that their output
is not constant but transient.
An envelope generator produces an output signal only "on demand." The demand is made by means of timing
signals called gates, and triggers.
envelope generators are controlled by gate
and trigger signals...
gate
trigger
ADSR
envelope
AR
envelope
3.5.4 Sample & Hold Processors
The idea of "sampling" a signal does not directly relate to any particular characteristic of audio events; instead, it
is an idea from electronics that has turned out to be useful for creating patterned control signals.
22