The hidden architecture of a song

A self-similarity heat-map of the music's harmony — bright off-diagonal stripes are repeats, blocks are sections. Click the map or the timeline to hear that moment.

The demo's form is A A' B A↑ C B A — the fourth section is A transposed up a fourth. It still matches the other A's because similarity is measured key-invariantly (max cosine over all 12 transpositions), the advance over a naive same-key SSM.