
Last year I made a little modification to STS’ harmonic oscillator, adding a cosine output so as to enable the XY oscilloscope shapes covered by Jerobeam Fenderson in one of his oscilloscope music videos. I finally got round to making another modification, this time making it possible for the frequency of each harmonic to be individually tuned instead of adjusting the phase. The perfectly tuned harmonics can be very beautiful but sometimes slight deviations can add a little movement and character to the sound – also visually – see Jerobeam’s video from around 5m30s.