Florence Elias's ninety-second clip is the thin-film equivalent of a Chladni plate. A vertical soap film is suspended at the end of a tube; a loudspeaker at the other end plays a piece of music; the film responds, and because its colours come from thin-film interference, every change in thickness shows up as a change in hue. Swirls split and merge in time with the music.
This is the mechanism worth understanding if you work with bubbles. The film's thickness varies over its surface — gravity drains it, so it is thinner at the top — and sound waves redistribute that thickness. You are not seeing the sound; you are seeing thickness, rendered in colour by interference.
Elias links a paper on the physics, then under submission, from the HAL archive. The music is by Choro de Rua. It is a small, precise, beautiful piece of work, and it deserves far more than its few thousand views.