madsr
madsr — Calculates the classical ADSR envelope using the linsegr mechanism.
Syntax
ares madsr iatt, idec, islev, irel [, idel] [, ireltim]
kres madsr iatt, idec, islev, irel [, idel] [, ireltim]
Initialization
iatt -- duration of attack phase
idec -- duration of decay
islev -- level for sustain phase
irel -- duration of release phase.
idel -- period of zero before the envelope starts
ireltim (optional, default=-1) -- Control release time after receiving a MIDI noteoff event. If less than zero, the longest release time given in the current instrument is used. If zero or more, the given value will be used for release time. Its default value is -1. (New in Csound 3.59 - not yet properly tested)
Please note that the release time was restricted to 32767/kr seconds in versions prior to 5.00; since then it has been (231-1)/kr.
Performance
The envelope is in the range 0 to 1 and may need to be scaled further. The envelope may be described as:
Picture of an ADSR envelope.
The length of the sustain is calculated from the length of the note. This means adsr is not suitable for use with MIDI events. The opcode madsr uses the linsegr mechanism, and so can be used in MIDI applications.
You can use other pre-made envelopes which start a release segment upon receiving a note off message, like linsegr and expsegr, or you can construct more complex envelopes using xtratim and release. Note that you do not need to use xtratim if you are using madsr, since the time is extended automatically.
![[Note]](images/note.png)
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Note |
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Times for iatt, idec and irel cannot be 0. If 0 is used, no envelope is generated. Use a very small value like 0.0001 if you need an instantaneous attack, decay or release. |
Examples
Here is an example of the madsr opcode. It uses the file madsr.csd.
Example 564. Example of the madsr opcode.
See the sections Real-time Audio and Command Line Flags for more information on using command line flags.
<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform ; Audio out Audio in No messages -odac -iadc -d ;;;RT audio I/O ; For Non-realtime ouput leave only the line below: ; -o madsr.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> /* Written by Iain McCurdy */ ; Initialize the global variables. sr = 44100 kr = 441 ksmps = 100 nchnls = 1 ; Instrument #1. instr 1 ; Attack time. iattack = 0.5 ; Decay time. idecay = 0 ; Sustain level. isustain = 1 ; Release time. irelease = 0.5 aenv madsr iattack, idecay, isustain, irelease a1 oscili 10000, 440, 1 out a1*aenv endin </CsInstruments> <CsScore> /* Written by Iain McCurdy */ ; Table #1, a sine wave. f 1 0 1024 10 1 ; Leave the score running for 6 seconds. f 0 6 ; Play Instrument #1 for two seconds. i 1 0 2 e </CsScore> </CsoundSynthesizer>
Here is another example of the madsr opcode, using midi input. It uses the file madsr-2.csd.
Example 565. second example of the madsr opcode.
<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform -odac -m0 --midi-key=4 --midi-velocity-amp=5 ; treat p4 and p5 as midi data ; For Non-realtime ouput leave only the line below: ; -o madsr-2.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> sr = 44100 ksmps = 32 nchnls = 2 0dbfs = 1 ; by Menno Knevel - 2021 instr 1 ; use score and treat p4 and p5 as midi data icps = cpsmidinn(p4) ; take midi note (p4) from score iveloc ampmidid p5, 92 ; take velocity (p5) from score ; att, dec, lvl, release kenv madsr .001, .2, 1, p6 prints "duration of note (%ds) + release (%2.1fs)\\n", p3, p6 ; asig vco2 iveloc, icps asig butlp asig, 2000 outs asig*kenv, asig*kenv endin </CsInstruments> <CsScore> ; note vel release s i 1 0 1 62 60 0 i 1 2 1 62 80 0 i 1 4 1 62 100 0 i 1 6 1 58 50 0 s i 1 1 1 62 60 0 i 1 3 1 62 80 .5 i 1 5 1 62 100 1.5 i 1 7 1 58 50 3 e </CsScore> </CsoundSynthesizer>
Here is an example for the adsr-group, comparing the different adsr opcodes. It uses the file adsr-group.csd.
Example 566. Example of the adsr group.
<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform -odac ;;;realtime audio out ;-iadc ;;;uncomment -iadc if realtime audio input is needed too ; For Non-realtime ouput leave only the line below: ; -o adsr-group.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> ; by Menno Knevel - 2021 sr = 44100 ksmps = 32 nchnls = 2 0dbfs = 1 ; both amplitude and filter use same ADSR curves instr 1 kenv adsr .01, .5, .5, p4 ; linear envelope asig vco2 kenv, 110 ; A+D+S+R = p3 asig rezzy asig, 500+(kenv*1000), 10 ; same curve but scaled outs asig, asig endin instr 2 ; midi behavior kenv madsr .01, .5, .5, p4 ; linear envelope asig vco2 kenv, 110 ; A+D+S = p3, then go into Release stage asig rezzy asig, 500+(kenv*1000), 10 ; same curve but scaled outs asig, asig endin instr 3 kenv xadsr .01, .5 , .5, p4 ; exponential envelope asig vco2 kenv, 110 ; A+D+S+R = p3 asig rezzy asig, 500+(kenv*1000), 10 ; same curve but scaled outs asig, asig endin instr 4 ; midi behavior kenv mxadsr .01, .5 , .5, p4 ; exponential envelope asig vco2 kenv, 110 ; A+D+S = p3, then go into Release stage asig rezzy asig, 500+(kenv*1000), 10 ; same curve but scaled outs asig, asig endin </CsInstruments> <CsScore> s i1 1 2 .01 ; same notes for everyone! i1 5 . .5 i1 9 . 1.5 s i2 1 2 .01 i2 5 . .5 i2 9 . 1.5 s i3 1 2 .01 i3 5 . .5 i3 9 . 1.5 s i4 1 2 .01 i4 5 . .5 i4 9 . 1.5 e </CsScore> </CsoundSynthesizer>