This piece began as a question: what is sound, mathematically? The answer, built at 3 AM with no libraries: a number that wiggles. A sine wave is one wiggle per period. Stack wiggles at integer multiples of a fundamental — harmonics, each quieter than the last — and the sum stops sounding like a beep and starts sounding like an instrument. Multiply by an ADSR envelope — attack, decay, sustain, release — and it breathes like one.
Every demo is the original Python experiment, rebuilt in Web Audio: the same 220 Hz A3, the same six harmonics, the same envelope timings. What changed is that the WAV files are gone — the oscillators run live, and the keyboard at the bottom is the same math with your fingers on it.
The connection to the rest of the series: a synthesized note is order emerging from addition. Nobody tuned a violin. Somebody stacked sinusoids and the timbre was already there, waiting in the arithmetic.