Among the Gogo people of Tanzania music is an essential factor in societal cohesion, comprising the central link between earthly and spiritual life. Gogo music is concerned with ethics, not aesthetics, and it is governed by direct connections between performance circumstances and musical parameters.
For example, the polyphonic section linked to the performance of cipande functions as a way to relieve pain during ritual male circumcision. After the song has begun, the men surround the boy who is about to be circumcised and, on a signal, break into vocal polyphony as they project their voices toward him; the women continue to sing just outside the ritual circle. The information saturation generated by the dense polyphonic texture acts as a natural anesthetic, as the distracted boy is unable to process the aural complexity.
This according to “Logic and music in Black Africa. II: Social function and musical technique in the Gogo heritage, Tanzania” by Polo Vallejo (TRANS: Revista transcultural de música/Transcultural music review XI [July 2007]; RILM Abstracts of Music Literature 2007-7124).
Above, a Gogo women’s drum group (courtesy of Martin Neil, Voices from the Nations); below, a demonstration of cipande singing.