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> -odac -d </CsOptions> <CsInstruments> ; Required settings for WebAudio: sr = 48000 ksmps = 128 nchnls = 2 nchnls_i = 1 ; sr = 48000 ; ksmps = 32 ; nchnls = 2 0dbfs = 1 gisine ftgen 0,0,2^12,10,1 instr 1 kamp adsr 0.1,0.01,1,10 ; THE MODULATION PARAMETERS krot linseg 0,p3,6.28 ; ROTATE kparam randc 2.5,0.1,0.993 ; CONTROL CURVEPARAMETER WITH CUBIC RANDOM kx linseg 0,p3/2,1,p3/2,0 ; MOVE HORIZONTAL THROUGH THE TERRAIN ky linseg 0,p3,1 ; MOVE VERTICAL THROUGH THE TERRAIN ; TRY THE OTHER CURVES AS WELL asigL wterrain2 0.2, 55*p4, kx, ky, 0.5, 0.4, krot, gisine, gisine, 5, kparam asigR wterrain2 0.2, -55*p4, kx, ky, 0.5, 0.4, krot, gisine, gisine, 5, kparam asigR dcblock asigL asigL dcblock asigR asigL butterlp asigL,9000 asigR butterlp asigR,9000 aL,aR reverbsc asigL, asigR, 0.7, 15000, 44100, 0.5, 1 outs aL*kamp*p5,aR*kamp*p5 endin </CsInstruments> <CsScore> i 1 0 300 1 1 i 1 1 300 7 0.4 i 1 2 299 [9/2] 0.4 i 1 3.1 296.9 [16/3] 0.45 i 1 4.3 295.7 [27/4] 0.5 i 1 6.9 292.1 6 0.5 e </CsScore> </CsoundSynthesizer>