In sound and music, an envelope describes how a sound changes over time. It may relate to elements such as amplitude (volume), frequencies (with the use of filters) or pitch. For example, a piano key, when struck and held, creates a near-immediate initial sound which gradually decreases in volume to zero.
Envelope generators, which allow users to control the different stages of a sound, are common features of synthesizers, samplers, and other electronic musical instruments. The most common form of envelope generator is controlled with four parameters: attack, decay, sustain and release (ADSR).
The Hammond Novachord in 1938 used an early implementation of an ADSR envelope. A seven-position rotary knob selects preset ADS parameter for all 72 notes; a pedal controls the release.[1]
The envelope generator was created by the American engineer Robert Moog in the 1960s. While experimenting with the first Moog synthesizers, composer Herbert Deutsch suggested Moog find a way to articulate the instrument 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.[2]
Following discussions with engineer and composer Vladimir Ussachevsky (then 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.[2]
ADSR
Schematic of ADSR
The most common kind of envelope generator has four stages: attack, decay, sustain, and release (ADSR).[3]
Attack is the time taken for initial run-up of level from nil to peak, beginning when the key is pressed.
Decay is the time taken for the subsequent run down from the attack level to the designated sustain level.
Sustain is the level during the main sequence of the sound's duration, until the key is released.
Release is the time taken for the level to decay from the sustain level to zero after the key is released.[4]
While attack, decay, and release refer to time, sustain refers to level.[3]
Some electronic musical instruments can invert the ADSR envelope, reversing the behavior of the normal ADSR envelope. During the attack phase, the modulated sound parameter fades from the maximum amplitude to zero then, during the decay phase, rises to the value specified by the sustain parameter. After the key has been released the sound parameter rises from sustain amplitude back to maximum amplitude.
Some envelopes, such as that of the Korg MS-20, have an extra parameter, hold. This holds notes at the sustain level for a fixed length of time before decaying. The General Instrument AY-3-8910sound chip includes only a hold time parameter; the sustain level is not programmable.
Another common variation in the same vein is the AHDSR (attack, hold, decay, sustain, release) envelope, in which the hold parameter controls how long the envelope stays at full volume before entering the decay phase. Multiple attack, decay and release settings may be found on more sophisticated models.
Certain synthesizers also allow for a delay parameter before the attack. Modern synthesizers, such as the Prophet '08, have DADSR (delay, attack, decay, sustain, release) envelopes. The delay setting determines the length of silence between hitting a note and the attack. Some software synthesizers, such as Image-Line's 3xOSC (included with their DAWFL Studio) have DAHDSR (delay, attack, hold, decay, sustain, release) envelopes.
A common feature on many synthesizers is an AD envelope (attack and decay only). This can be used to control e.g. the pitch of one oscillator,[5] which in turn may be synchronized with another oscillator by oscillator sync.
^ abVail, Mark (2014). The Synthesizer: A Comprehensive Guide to Understanding, Programming, Playing, and Recording the Ultimate Electronic Music Instrument. OUP USA. ISBN9780195394894.
^"How to use basic ADSR filter envelope parameters". MusicRadar. June 21, 2013. Retrieved 2018-12-16.
^Synthesizer technique. H. Leonard Books. 1987. p. 64. OCLC 1036880013.
January 20, 2023
envelope, music, sustain, redirects, here, other, uses, sustain, disambiguation, sound, music, envelope, describes, sound, changes, over, time, relate, elements, such, amplitude, volume, frequencies, with, filters, pitch, example, piano, when, struck, held, cr. Sustain redirects here For other uses see Sustain disambiguation In sound and music an envelope describes how a sound changes over time It may relate to elements such as amplitude volume frequencies with the use of filters or pitch For example a piano key when struck and held creates a near immediate initial sound which gradually decreases in volume to zero Envelope generators which allow users to control the different stages of a sound are common features of synthesizers samplers and other electronic musical instruments The most common form of envelope generator is controlled with four parameters attack decay sustain and release ADSR Contents 1 Development 2 ADSR 3 Other envelopes 4 See also 5 ReferencesDevelopment Edit The ADSR envelope controls of a Korg ARP Odyssey synthesizer The Hammond Novachord in 1938 used an early implementation of an ADSR envelope A seven position rotary knob selects preset ADS parameter for all 72 notes a pedal controls the release 1 The envelope generator was created by the American engineer Robert Moog in the 1960s While experimenting with the first Moog synthesizers composer Herbert Deutsch suggested Moog find a way to articulate the instrument 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 2 Following discussions with engineer and composer Vladimir Ussachevsky then 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 2 ADSR Edit Schematic of ADSRThe most common kind of envelope generator has four stages attack decay sustain and release ADSR 3 Attack is the time taken for initial run up of level from nil to peak beginning when the key is pressed Decay is the time taken for the subsequent run down from the attack level to the designated sustain level Sustain is the level during the main sequence of the sound s duration until the key is released Release is the time taken for the level to decay from the sustain level to zero after the key is released 4 While attack decay and release refer to time sustain refers to level 3 Other envelopes EditThis section needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed January 2020 Learn how and when to remove this template message Some electronic musical instruments can invert the ADSR envelope reversing the behavior of the normal ADSR envelope During the attack phase the modulated sound parameter fades from the maximum amplitude to zero then during the decay phase rises to the value specified by the sustain parameter After the key has been released the sound parameter rises from sustain amplitude back to maximum amplitude 8 step envelope on Casio CZ series Some envelopes such as that of the Korg MS 20 have an extra parameter hold This holds notes at the sustain level for a fixed length of time before decaying The General Instrument AY 3 8910 sound chip includes only a hold time parameter the sustain level is not programmable Another common variation in the same vein is the AHDSR attack hold decay sustain release envelope in which the hold parameter controls how long the envelope stays at full volume before entering the decay phase Multiple attack decay and release settings may be found on more sophisticated models Certain synthesizers also allow for a delay parameter before the attack Modern synthesizers such as the Prophet 08 have DADSR delay attack decay sustain release envelopes The delay setting determines the length of silence between hitting a note and the attack Some software synthesizers such as Image Line s 3xOSC included with their DAW FL Studio have DAHDSR delay attack hold decay sustain release envelopes A common feature on many synthesizers is an AD envelope attack and decay only This can be used to control e g the pitch of one oscillator 5 which in turn may be synchronized with another oscillator by oscillator sync See also EditEnvelope waves Envelope detectorReferences Edit Cirocco Phil 2006 The Novachord Restoration Project Cirocco Modular Synthesizers a b Pinch Trevor Trocco Frank 2004 Analog Days The Invention and Impact of the Moog Synthesizer Harvard University Press pp 43 ISBN 978 0 674 01617 0 a b Vail Mark 2014 The Synthesizer A Comprehensive Guide to Understanding Programming Playing and Recording the Ultimate Electronic Music Instrument OUP USA ISBN 9780195394894 How to use basic ADSR filter envelope parameters MusicRadar June 21 2013 Retrieved 2018 12 16 Synthesizer technique H Leonard Books 1987 p 64 OCLC 1036880013 Retrieved from https en wikipedia org w index php title Envelope music amp oldid 1091315685, wikipedia, wiki, book, books, library,
