Tonality Algorithms: Determining Keys, Spellings, Boundaries, and Expectation

Start: 02/25/2010 - 4:15pm
End  : 02/25/2010 - 5:15pm

Statistics/OR/Math Finance Seminar

Elaine Chew, USC


Tonality is the system of inter-pitch relations that frames our understanding of tonal music, which encompasses most of the music that we hear. Tonality is why we hear some pitches as being more stable than others; it is why we know when a phrase has ended, the context has changed, or some notes sound surprising. A composer uses tonality to shape a composition; tonal structures guide a performer’s choreography of a musical interpretation; and, tonality influences a listener’s perception of expectation and surprise.

Mathematical models for tonality, and computational algorithms to determine the structures in tonality, are fundamental tools for understanding music perception and cognition, for building systems for music information retrieval, and for designing interactive systems for live performance and for computer games with music.

This talk will introduce the Spiral Array model for tonality, and associated algorithms for key finding, pitch spelling, and boundary detection. The Spiral Array underlies the MuSA.RT interactive system for real-time tonal analysis and visualization. Using MuSA.RT, music examples will illustrate the computational algorithms, and concepts of expectation and surprise.

MuSA.RT is joint work with Alexandre R. J. François.

Sprague 3rd Floor Seminar Space Harvey Mudd College Refreshments at 4pm