Gamelan with male groups. In the twenty-five countries outside Indonesia that have gamelan, music performed in a concert context or as part of ceremonies for expat communities may also accompany dance or "wayang". The tuning and construction of a gamelan orchestra is a complex process. Javanese gamelan use two tuning systems: "sléndro" and "pélog". There are other tuning systems such as "degung" (exclusive to Sunda, or West Java), and "madenda" (also known as "diatonis", similar to a European natural minor scale). In central Javanese gamelan, "sléndro" is a system with five notes to the octave, with large intervals, while "pélog" has
Gamelan in present-day Central Java are shown below: Varieties of gamelan are distinguished by their collection of instruments and use of voice, tunings, repertoire, style, and cultural context. In general, no two gamelan ensembles are the same, and those that arose in prestigious courts are often considered to have their own style and tuning. Certain styles may also be shared by nearby ensembles, leading to a regional style. The varieties are generally grouped geographically, with the principal division between the styles favored by the Balinese, Javanese, and Sundanese peoples. The Madurese also had their own style of gamelan, although it is