Mbenga–Mbuti Pygmy music consists of up to four parts and can be described as an "ostinato with variations" similar to a passacaglia in that it is cyclical. It is based on repetition of periods of equal length that each singer divides using different rhythmic figures specific to different repertoires and songs. This creates a detailed surface and endless variations not only of the same period repeated but of various performances of the same piece of music. As in some Balinese gamelan music these patterns are based on a super-pattern which is never heard. The Pygmies themselves do not learn or think of their music in this theoretical framework, but learn the music growing up.