idea
Gamelan and ombak
Gamelan orchestras from Java and Bali are made mostly of bronze metallophones and gongs. Bronze bars do not have neatly spaced harmonics like strings, so the intervals that sound good on them are different. Gamelans use two scale systems, sléndro with five notes and pélog with seven, and each set of instruments is tuned to itself, so no two gamelans sound exactly alike. In Bali, instruments are made in pairs tuned slightly apart, so that together they beat and shimmer. This effect is called ombak, which means wave.