Exploring African Tone Scales

Key-finding is a central topic in Western music analysis and development of MIR tools. However, most approaches rely on the Western 12-tone scale, which is not universally used. African music does not follow a fixed tone scale. In order to classify and study African tone scales, we developed a system in which the pitch is first analyzed on a continuous scale. Peak analysis is then applied on these data to extract the actual scale used. This system has been applied to a selection of African music, it allows us to look for similarities using cross-correlation. Thus it provides an interesting tool for query-by-example and database management in collections of ethnic music which can not be simply classified according to keys. Next to this the data can be used for ethnomusicological research. The study of the intervals used in this collection, e.g., gives us evidence for Western influence, with recent recordings having a tendency to use more regular intervals.