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 -odac ; -iadc ;;;RT audio out ; For Non-realtime ouput leave only the line below: ; -o Mixer.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 katt expon 0.01, p3, 1 ;create an attack aout poscil .7, 440,1 MixerSetLevel 1, 3, katt ;impose attack on the gain level MixerSend aout, 1, 3, 0 ;send to channel 0 endin instr 2 aout vco2 .5, 110 ;saw wave MixerSetLevel 2, 3, .25 ;set level to .25 of vco2 MixerSend aout, 2, 3, 1 ;send to channel 1 endin instr 3 ;mix instr.1 and 2 with reverb kgain1 MixerGetLevel 1,3 ;get level form buss 3 kgain2 MixerGetLevel 2,3 ;get level form buss 3 a1 MixerReceive 3,0 ;receive channel 0 a2 MixerReceive 3,1 ;receive channel 1 aout = a1*kgain1+a2*kgain2 ;mix them aoutL, aoutR reverbsc aout, aout, 0.85, 12000 ;add a nice reverb outs aoutL, aoutR MixerClear endin </CsInstruments> <CsScore> f1 0 4096 10 1 i1 0 2 i2 0 2 i3 0 8 ;reverb stays on for 8 sec. e </CsScore> </CsoundSynthesizer>