The genggong is a kind of jaw harp used in the music of Bali

Music of Bali

Bali is an Indonesian island that shares in the gamelan and various other Indonesian musical styles. Bali, however, has its own techniques and styles, including kecak, a form of singing that imitates the sound of monkeys...

. It consists of a wooden frame and tongue cut from a single piece of the leaf stem of the sugar palm

Sugar palm

Sugar palm is a common name for several species of palms used to produce sugar.*Arenga pinnata *Borassus flabellifer*Caryota urens*Cocos nucifera...

. The left end is held firmly against the cheek, while a string tied to the right end is jerked rhythmically to set the tongue into motion (in contrast to other jaw harps in which the tongue itself is plucked to produce sound). Different harmonic

Harmonic

A harmonic of a wave is a component frequency of the signal that is an integer multiple of the fundamental frequency, i.e. if the fundamental frequency is f, the harmonics have frequencies 2f, 3f, 4f, . . . etc. The harmonics have the property that they are all periodic at the fundamental...

s are produced by pronouncing different vowel sounds.

Very much a folk instrument

Folk instrument

A folk instrument is an instrument that developed among common people and usually doesn't have a known inventor. It can be made from wood, metal or other material. It is a part of folk music...

, genggong was traditionally played only as a solo instrument or with small numbers of other genggong as informal entertainment. Since the 1930s, however, genggong has often featured in gamelan genggong, a larger ensemble of several genggong together with suling

Suling

A suling or Seruling is an Indonesian bamboo ring flute. It is used in gamelan ensembles.Depending on the regional genre, a suling can be tuned into different scales...

and percussion instruments.