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 -iadc -d ;;;RT audio I/O ; For Non-realtime ouput leave only the line below: ; -o zkr.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> ; Required settings for WebAudio: sr = 48000 ksmps = 128 nchnls = 2 nchnls_i = 1 ; Initialize the global variables. ; sr = 44100 ; kr = 4410 ; ksmps = 10 ; nchnls = 1 ; Initialize the ZAK space. ; Create 1 a-rate variable and 1 k-rate variable. zakinit 1, 1 ; Instrument #1 -- a simple waveform. instr 1 ; Linearly vary a k-rate signal from 440 to 880. kline line 440, p3, 880 ; Add the linear signal to zk variable #1. zkw kline, 1 endin ; Instrument #2 -- generates audio output. instr 2 ; Read zk variable #1. kfreq zkr 1 ; Use the value of zk variable #1 to vary ; the frequency of a sine waveform. a1 oscil 20000, kfreq, 1 ; Generate the audio output. out a1 ; Clear the zk variables, get them ready for ; another pass. zkcl 0, 1 endin </CsInstruments> <CsScore> ; Table #1, a sine wave. f 1 0 16384 10 1 ; Play Instrument #1 for one second. i 1 0 1 ; Play Instrument #2 for one second. i 2 0 1 e </CsScore> </CsoundSynthesizer>