Development synthesizer The envelope generator was created by the American engineer
Robert Moog, the creator of the
Moog synthesizer, in the 1960s. The composer
Herbert Deutsch suggested Moog find a way to articulate his synthesizer so notes did not simply trigger on and off. Moog wired a
doorbell button to the synthesizer and used a
capacitor to store and slowly release
voltage produced from hitting a key. He refined the design to remove the need to push a separate button with every keypress, with two switches on every key: one to produce the control voltage determining pitch and the other to trigger the envelope generator. The envelope generator became a standard feature of synthesizers. Following discussions with the engineer and composer
Vladimir Ussachevsky, the head of the
Columbia-Princeton Electronic Music Center, in 1965, Moog developed a new envelope module whose functions were described in f T1 (attack time), T2 (initial decay time), ESUS (sustain level), and T3 (final decay time). These were later simplified to the modern ADSR form (attack time, decay time, sustain level, release time) by
ARP. •
Attack is the time taken for the rise of the level from nil to peak. •
Decay is the time taken for the level to reduce from peak to the sustain level. •
Sustain is the level maintained until the key is released. •
Release is the time taken for the level to decay to nil. While attack, decay, and release refer to time, sustain refers to level. which in turn may be synchronized with another oscillator by
oscillator sync. == See also ==