Bedamuni drum New Guinea

Nomad River drum (iribu), Bedamuni / Bedamini people - New Guinea / Trommel Neuguinea

"Properly tuned, the drum has to sound two-toned, somewhat like `ba-u´(from low to high) otherwise the performance is not right. This sound is said to be the voice of Awamuni, the culture hero that gave the Bedamuni their cultural identity.
An intriguing detail is that drum rhythm and the bodily movement of the performer should not be in phase.
In fact, when a ceremony has a number of performers (sometimes three or four) they too will not drum in phase.
This, together with burst of singing from groups of young girls in the men´s sleeping area,
makes the whole performance completely cacophonic to the untrained ear and eye, yet strangely impressive."
excerpt from the book:
Living Spirits with Fixed Abodes - edited by Barry Craig, page 192.

Barry Craig (Editor) - Living Spirits with Fixed Abodes - University of Hawai'i Press - 2011
Steven Feld - Sound as a symbolic system: the Kaluli drum. Bikmaus 4(3):78-89.
Edward L. Schieffelin - The Sorrow of the Lonely and the Burning of the Dancers. New York: St. Martin's Press. 1976
Edward L. Schieffelin - Kaluli Dance (with Steven Feld), In The International Encyclopedia of Dance. Oxford University Press 1998.