Wela

Colotomy is an Indonesian description of the rhythmic and metric patterns of gamelan music. It refers to the use of specific instruments to mark off nested time intervals, or the process of dividing rhythmic time into such nested cycles. In the gamelan, this is usually done by gongs of various size: the kempyang, ketuk, kempul, kenong, gong suwukan, and gong ageng. The fast-playing instruments, kempyang and ketuk, keep a regular beat. The larger gongs group together these hits into larger groupings, playing once per each grouping. The largest gong, the gong ageng, represents the largest time cycle and generally indicates that the preceding section will be repeated, or the piece will move on to a new section.

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