Among the many gamelans (literally "orchestras") present in Indonesia, the gong kebyar gamelan is today the most widespread orchestral formation on the island of Bali, where it is associated with dance, theatre and various rituals in which music plays a predominant role. Composed mainly of metallophone percussion instruments, the gamelan allows us to address issues related to coordination within an ensemble, polyrhythm and interaction in the performance, and to reflect on the very notion of an orchestra.