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If a guitar player for instance strums one single chord, we will hear a “ploink“-
sound, which will end abruptly as soon as he lays his finger on the chord.
The sound wave starts suddenly with a “pl” in “ploink” (Attack), quickly de-
creasing (Decay), followed by a constant phase (“oin” = Sustain) and suddenly
stopped by a finger at the chord (“k“ = Release).
The synthesizer will be able to imitate any acoustic source by generating a
sound wave and varying the duration of these four parameters for this sound
wave.
Varying the 4 parameters in a noise generator wave results in a good imitation
of percussion instruments and adjusting the filter parameters for a noise gen
-
erator wave allows us to imitate almost any whistling sound.
Overview of the standard synthesizer modules and parameters:
Oscillator:
A wave generator providing a programmable frequency and wave amplitude
Envelope:
The wave amplitude as a function of time
Filter:
A module for emphasizing, weakening, or removing a frequency spectrum
Lowfrequency oscillator:
A slowly varying and adjustable signal source, used to control a pitch or volume
of an oscillator.
Attack:
A „stroke“, suddenly raising the sound wave up to a maximum level.
Decay:
Decreasing phase (from a maximum to a constant level).
Sustain:
A constant level phase
Release:
Extinction phase of a sound wave
