Javanese tradition claims that gamelan music dates back from well before the influences from India and Hinduism.

In the beginning the god Sang Hyang Guru ruled as King of all Java, in a palace at the top of a mountain in central Java. He needed a signal by which he could summon all the gods together, so he made a gong tuned to a certain pitch. As the different messages beaten on the gong became more complicated, he made a second gong, tuned to another pitch. In time he made a third to simplify matter further, and three tones of the original gamelan set, named 'Lokananta' (King of the World) were formed from the three pitches of the gongs. This gamelan set was supposed to have been created in the Javanese year 167 (around 230 AD).

The two major cities of central Java, Yogyakarta and Surakarta (or Solo), are both major cultural centres to this day. Each still has an ancient gamelan, in the archaic three-toned scale, dating from the twelfth century. These are 'loud style' gamelans, consisting exclusively of gongs, kettle gongs and metallophones, with the chief melodic instrument the rack of kettle gongs known as a bonang. The gongs range up to 125cm in width, the largest requiring a 12kg mallet to play it.

As well as the loud style gamelan, which was used for outdoor functions, a soft style of music developed which was used in particular to accompany the wayang kulit (shadow puppet play). The soft style gamelan included the original large gongs and kettle gongs, but not the bonangs. In place of metallophones with thick bars, instruments with thin metal plates of resonating bamboo tubes were used, with a gentle attack and sustained sound.

Over time new instruments were introduced into the soft ensemble - the gambang (wooden xylophone), suling (bamboo flute) and the bowed two stringed rebab (of arabic origin).

The modern central Javanese gamelan came about in the seventeenth century when the two ensembles came to be mixed, producing a single music with a huge range of sounds and textures.