Gong siyem

The gong ageng (or gong gedhe in Ngoko Javanese, means large gong) is a musical instrument. It is the largest of the bronze gongs in the Javanese and Balinese gamelan orchestra and the only large gong that is called gong in Javanese. Unlike the more famous Chinese or Turkish tam-tams, Indonesian gongs have fixed, focused pitch, and are dissimilar to the familiar crash cymbal sound. It is circular, with a conical, tapering base of diameter smaller than gong face, with a protruding polished boss where it is struck by a padded mallet. Gongs with diameter as large as 135 centimeters (53 inches) have been created in the past, but gongs larger than about 80 centimeters (31 inches) are more common especially to suit the budget of educational institutions.

There is at least one large gong in each gamelan, but two are common and older gamelans may have three or more. The gong ageng usually has its own name, which may be bestow upon the entire set of instruments. The gong ageng is considered the most important instrument in a gamelan ensemble: the soul or spirit of the gamelan is said to live in the gong.Gong ageng are often proffered ritual offerings of flowers, food, and/or and incense before performances or each Thursday evening to appease spirits believed to live in and around it.

Commonly, less expensive iron gong ageng or a slit-type gong are made to fulfill the role of the bronze gong, though at the loss of sound quality- for poorer regions and villages. The cost of expertly pure cast & beaten bronze has seen a rise in bronze-plated and bronze-laminated iron gongs created for the undiscerning expatriate.

Traditionally, it is the first of the instruments to be made. A highly skilled gong-smith will smelt and cast, then supervises the hammering process, but will be solely responsible for the final fine tuning of the gong ageng pitch- the rest of the ensemble is tuned (and named) according to the qualities of the gong ageng. It is the single most costly and lengthy item to fabricate- and often requires multiple re-castings due to stress-cracks created in the beating process of forming it and undesired tonal or timbre qualities. The pitch desired is very deep, distinctly pitched rumble that sound like thunder or the "rolling waves of the sea". Slight differences in the opposite halves of a gong create a desired "beating" in the sound. It is named according to subjective poetic descriptive images for different speeds of beats, comparing slow beats with waves of water and faster beats with Bima’s laughter (Bima is one of the Pandawa brothers in the Mahabharata epic).

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Wikipedia