Cengkok (old orthography: chengkok) are patterns played by the elaborating instruments in the Javanese gamelan. Typically they are melodic patterns that lead to the seleh, following the rules of the pathet of the piece. Gamelan - Indonesian Embassy in Canberra A gamelan is a kind of musical ensemble of Indonesian origin typically featuring a variety of instruments such as metallophones, xylophones, drums, and gongs; bamboo flutes, bowed and plucked strings, and vocalists may also be included. ... The pathet (Javanese spelling; also patet) is an organizing concept in gamelan music. ...

The most elaborate cengkok repertoire is that of the gendér barung. The gambang and siter, on the other hand, do not have such formalized sets of cengkok, and therefore may vary more from performer to performer. A gambang is a metallophone-like percussive instrument of Indonesian origin, with wooden bars as opposed to the metallic ones in a Western metallophone; it forms part of a gamelan ensemble. ... Celempung at the Indonesian Embassy in Australia The siter and celempung are plucked string instruments used in Javanese gamelan. ...

Most cengkok derive from the vocal repertoire, and many have names that originally came from lyrics, like the well-known Ayu kuning. They may incorporate pre-existent melodic patterns through a process of centonization. Centonization refers to the practice of composing melodies based on pre-existing melodic figures and formulas. ...