mxadsr
mxadsr — Calculates the classical ADSR envelope using the expsegr mechanism.
Syntax
ares mxadsr iatt, idec, islev, irel [, idel] [, ireltim]
kres mxadsr 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 (optional, default=0) -- 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)
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 exponential 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. The opcode mxadsr is identical to madsr except it uses exponential, rather than linear, line segments.
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 mxadsr, since the time is extended automatically.
mxadsr is new in Csound version 3.51.
Examples
Here is an example of the mxadsr opcode. It uses the file mxadsr.csd.
Example 650. Example of the mxadsr 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 -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 mxadsr-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 mxadsr .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 1 i 1 5 1 62 100 3 i 1 7 1 58 50 5 e </CsScore> </CsoundSynthesizer>
Here is an example for the adsr-group, comparing the different adsr opcodes. It uses the file adsr-group.csd.
Example 651. 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>