Angklung is a musical instrument made out of two bamboo tubes attached to a bamboo frame. The tubes are carved so that they have a resonant pitch when struck. The two tubes are tuned to octaves. The base of the frame is held with one hand while the other hand shakes the instrument rapidly from side to side. This causes a rapidly repeating note to sound. Thus each of three or more angklung performers in an ensemble will play just one note and together complete melodies are produced. Angklung is popular throughout Southeast Asia, but originated from Indonesia and it has been used and played by the Sundanese since the ancient times.
In the Hindu period and the era of the Kingdom of Sunda, the people of Sunda, as West Java is called, used the angklung to signal the time for prayer. Later, in Kingdom of Sunda these instruments were used as martial music in the Bubat War (Perang Bubat) as told in the Kidung Sunda.
The angklung functioned to build community spirit. It was used by the Sundanese until the colonial era (Dutch East Indies, V.O.C). At that time, the Dutch East Indies government forbade the playing the angklung. Because of this, the popularity of the instrument decreased and it came to be played only by children.
The angklung got more international attention when Daeng Soetigna, from Bandung, West Java, expanded angklung tuning not only to play traditional pélog or sléndro scales, but also the diatonic scale in 1938. Since then, angklung is often played together with other western music instruments in an orchestra. One of the first well-known performances of angklung in an orchestra was during the Bandung Conference in 1955. A few years later, Udjo Ngalagena, a student of Daeng Soetigna, opened his "Saung Angklung" (House of Angklung) in 1966 as a centre for its development.
In Bali, an ensemble of angklung is called gamelan angklung (anklung). While the ensemble gets its name from the bamboo shakers, these days most compositions for Gamelan Angklung do not use them. An ensemble of mostly bronze metallophones is used instead, generally with about 20 musicians.
While the instrumentation of gamelan angklung is similar to gamelan gong kebyar, it has several critical differences. First, the instruments are tuned to a 5-tone slendro scale, though actually most ensembles use a four-tone mode of the five-tone scale played on instruments with four keys. An exception is the five-tone angklung from the north of Bali. But even in four-tone angklung groups, the flute players will occasionally touch on the fifth implied tone. Secondly, whereas many of the instruments in gong kebyar span multiple octaves of its pentatonic scale, mosts gamelan angklung instruments only contain one octave, although some five-tone ensembles have roughly an octave and a half. The instruments are considerably smaller than those of the gong kebyar.
Gamelan angklung is often heard in Balinese temples, where it supplies musical accompaniment to temple anniversaries (odalan). It is also characteristic of rituals related to death, and therefore connected in Balinese culture to the invisible spiritual realm and transitions from life to death and beyond. Because of its portability, gamelan angklung may be carried in processions while a funeral bier is carried from temporary burial in a cemetery to the cremation site. The musicians also often play music to accompany the cremation ceremony. Thus many Balinese listeners associate angklung music with strong emotions evoking a combination of sacred sweetness and sadness.
The structure of the music is similar to gong kebyar, although employing a four tone scale. Jublag and jegog carry the basic melody, which is elaborated by gangsa, reyong, ceng-ceng, drum, and flute. A medium sized gong, called kempur, is generally used to punctuate a piece's major sections.
Most older compositions do not employ gong kebyar's more ostentatious virtuosity and showmanship. Recently many Balinese composers have created kebyar-style works for gamelan angklung or have rearranged kebyar melodies to fit the angklung's more restricted four tone scale. These new pieces often feature dance, so the gamelan angklung is augmented with more gongs and heavier gongs. Additionally, some modern composers have created experimental instrumental pieces for the gamelan angklung.