Nine oscillators tuned to very small offsets relative to the main pitch create an effect called “Risset’s harmonic arpeggio”. Pitch, arpeggiation offset and amplitude controls; six waveforms with morphing; stereo mode has optional cross-panning with speed control; optional dual mono mode (Mono 1: Risset arpeggio; Mono 2: waveform oscillator).
Code/details:
https://github.com/DaveSeidel/music-src/tree/master/Nebulae/instr/Risset_Harmonic_Oscillator
NOTE: v1.1 fixes a bug that caused a bootloop, so please use the new version.