- Don Niles
Concussion (dilating or retreating) reed pipe of the Keraki (Nambu) people of Papua New Guinea. A 60-cm-long bamboo tube is closed at one end by a node and is open at the other. From the open end, a slit is made longitudinally down to the node. The player puts his mouth completely over the open end and blows, causing the split sides to vibrate and emit a harsh, shrill sound. ...