Tam-tam

A gong (from Javanese, Indonesian, Malay: gong; Chinese: ; pinyin: luó; Thai: ฆ้อง Khong; Vietnamese: cồng chiêng) is an African, East and South East Asian musical percussion instrument that takes the form of a flat, circular metal disc which is hit with a mallet. It originated in China and later spread to Southeast Asia, and it can also be used in the percussion section of Western symphony orchestra.

Gongs are broadly of three types. Suspended gongs are more or less flat, circular discs of metal suspended vertically by means of a cord passed through holes near to the top rim. Bossed or nipple gongs have a raised centre boss and are often suspended and played horizontally. Bowl gongs are bowl-shaped, and rest on cushions and belong more to bells than gongs. Gongs are made mainly from bronze or brass but there are many other alloys in use.

Gongs produce two distinct types of sound. A gong with a substantially flat surface vibrates in multiple modes, giving a "crash" rather than a tuned note. This category of gong is sometimes called a tam-tam to distinguish it from the bossed gongs that give a tuned note. In Indonesian gamelan ensembles, some bossed gongs are deliberately made to generate in addition a beat note in the range from about 1 to 5 Hz. The use of the term "gong" for both these types of instrument is common.

Suspended gongs are played with hammers and are of two main types: flat faced discs either with or without a turned edge, and gongs with a raised centre boss. In general, the larger the gong, the larger and softer the hammer. In Western symphonic music the flat faced gongs are generally referred to as tam-tams to distinguish them from their bossed counterparts, and the term "gong" is reserved to the bossed type only. The gong has been a Chinese instrument for millennia. Their first use may have been to signal peasant workers in from the fields as some gongs are loud enough to be heard from up to five miles away. In Japan, they are traditionally used to start the beginning of sumo wrestling contests.

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