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 -odac -M1 ;;;realtime audio out and midi in ;-iadc ;;;uncomment -iadc if realtime audio input is needed too ; For Non-realtime ouput leave only the line below: ; -o mididefault.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 mididefault 60, p3 ;ensures that a MIDI-activated instrument will have a positive p3 field midinoteoncps p4, p5 ;puts MIDI key translated to cycles per second into p4, and MIDI velocity into p5 kvel = p5/127 ;scale midi velocity to 0-1 kenv madsr 0.5, 0.8, 0.8, 0.5 ;amplitude envelope multiplied by asig pluck kenv*kvel, p4, p4, 2, 1 ;velocity outs asig, asig endin </CsInstruments> <CsScore> f 0 30 ;runs for 30 seconds f 2 0 4096 10 1 i 1 0 2 440 100 ; play these notes from score as well i 1 + 2 1440 100 e </CsScore> </CsoundSynthesizer>