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<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform ; Audio out Audio in Silent MIDI in -odac -iadc -d -M0 ;;;realtime I/O </CsOptions> <CsInstruments> ; Required settings for WebAudio: sr = 48000 ksmps = 128 nchnls = 2 nchnls_i = 1 ;xtratim example by Jonathan Murphy Dec. 2006 ; sr = 44100 ; ksmps = 10 ; nchnls = 2 ; sine wave for oscillators gisin ftgen 1, 0, 4096, 10, 1 ; set volume initially to midpoint ctrlinit 1, 7,64 ;;; simple two oscil, two envelope synth instr 1 ; frequency kcps cpsmidib ; initial velocity (noteon) ivel veloc ; master volume kamp ctrl7 1, 7, 0, 127 kamp = kamp * ivel ; parameters for aenv1 iatt1 = 0.03 idec1 = 1 isus1 = 0.25 irel1 = 1 ; parameters for aenv2 iatt2 = 0.06 idec2 = 2 isus2 = 0.5 irel2 = 2 ; extra (release) time allocated xtratim (irel1>irel2 ? irel1 : irel2) ; krel is used to trigger envelope release krel init 0 krel release ; if noteoff received, krel == 1, otherwise krel == 0 if (krel == 1) kgoto rel ; attack, decay, sustain segments atmp1 linseg 0, iatt1, 1, idec1, isus1 , 1, isus1 atmp2 linseg 0, iatt2, 1, idec2, isus2 , 1, isus2 aenv1 = atmp1 aenv2 = atmp2 kgoto done ; release segment rel: atmp3 linseg 1, irel1, 0, 1, 0 atmp4 linseg 1, irel2, 0, 1, 0 aenv1 = atmp1 * atmp3 ;to go from the current value (in case aenv2 = atmp2 * atmp4 ;the attack hasn't finished) to the release. ; control oscillator amplitude using envelopes done: aosc1 oscil aenv1, kcps, gisin aosc2 oscil aenv2, kcps * 1.5, gisin aosc1 = aosc1 * kamp aosc2 = aosc2 * kamp ; send aosc1 to left channel, aosc2 to right, ; release times are noticably different outs aosc1, aosc2 endin </CsInstruments> <CsScore> f 0 3600 ;dummy table to wait for realtime MIDI events </CsScore> </CsoundSynthesizer>