This should play if your Web browser has WebAssembly enabled (most do). Most examples will play unless they need to load files. The first time you click Play, Csound will spend a few seconds loading, then play. You can edit this code and replay it.
<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform ; Audio out Audio in No messages -odac ;;;realtime audio I/O ; For Non-realtime ouput leave only the line below: ; -o -.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> ; Required settings for WebAudio: sr = 48000 ksmps = 128 nchnls = 2 nchnls_i = 1 ; sr = 44100 ; ksmps = 32 ; nchnls = 2 0dbfs = 1 instr 1 idur = p3 iatt = p4 idec = p5 isus = p3-iatt-idec ;calculate sustain time from subtracting attack and decay printf_i "sutain time= note duration - attack - decay --> %.1f-%.1f-%.1f = %.1f\n", 1, idur, iatt, idec, isus kenv expseg 0.01, iatt, 1, isus, 1, idec, 0.01 ;envelope asig poscil 1*kenv, 200, 1 outs asig, asig endin </CsInstruments> <CsScore> f 1 0 4096 10 1 ;sine wave ; attack decay i 1 0 3 .1 .2 i 1 4 3 .5 1.5 i 1 8 5 4 .5 e </CsScore> </CsoundSynthesizer>