“Most of the instruments of a Javanese gamelan ensemble are metallophones –percussion instruments made of brass, iron, or bronze (bronze instruments generally have the best sound). A typical ensemble also has drums, wooden bar percussion instruments, plucked string instruments, bowed string instruments, and bamboo flutes. Gamelan music is a communal art form; playing the music requires a strong sense of rhythm and attention to the music of the whole group. Javanese gamelan does not stress virtuosic displays of musical talent.
A set of gamelan is a whole entity, one cannot play instruments of different sets together (because of tuning variations) and one cannot simply play one instrument and get a sense of Javanese gamelan music. Traditionally in Java, gamelan sets have even been thought of to have a spirit of their own.
To Western ears, gamelan music sounds very different from “normal” music. Instead of major and minor scales, one will hear music in two laras, or scales: sléndro and pélog. To some Westerners with a deeply rooted sense of pitch, gamelan music may seem “out of tune,” in fact, even the instruments of different gamelan ensembles do not share exactly the same intervallic scale structure. This variety lends a character to each gamelan set and many gamelan are named to reflect their character. Gamelan music in Java has had a much longer, richer tradition of percussion music than Western music has had.”
– Bern Jordan