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.