Torus Animations

Here are animations of how music moves around in tonal space, which can be represented on a torus (the shape of a bagel). The surface of the torus is flattened so that it can be viewed in two dimensions. This means that in each of the images below, the top and bottom edges are the same, as are the left and right edges.

A very brief explanation of what the movies represent

Each movie is generated by starting with a .wav file of the piece of music. The audio waveform is then digitally processed in a series of steps that model neural responses in the auditory periphery, extract periodicity pitch, and finally project the time-varying periodicity pitch distributions to the surface of a torus. The toroidal surface represents tonal space that is encountered in Western tonal music. The letters on the image in the movies correspond to the 24 major (uppercase letters) and minor (lowercase letters) keys. As the harmonies in the music change, so does the activation pattern on the toroidal surface.

You will need the Quicktime plugin (included with the free player) to view these, which you can download by following this link. Click on an image or corresponding title to view the animation.

Otis Redding - Sittin' On the Dock of the Bay Justin TimberLake - Rock Your Body
Ace of Base - Cruel Summer Alicia Keys - If I Ain't Got You
Norah Jones - Don't Know Why Aerosmith - Jaded
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