I hope to start making my way through your collection of “Audio Illusions” videos! Have you done any on the “illusion” of tuning? (Why certain intervals sound better than others, and why certain tunings might sound better to the ear than others)? I haven’t dived into that topic yet (different types of tuning and which might be best for a melodica) but I’m interested. By the way, on Youtube I’m “Doctor Melodica” and you might find this line of experimentation interesting: https://www.youtube.com/watch?v=fZU-EA6584I&t=368s