Percussion

Percussion instruments are music instruments played by being struck, shaken, rubbed or scraped, hence the "percussive" name. They are perhaps the oldest form of musical instruments, rivaled only by vocal. Percussion instruments play not only rhythm, but also melody and harmony. more...

Music for pitched percussion instruments can be notated on a staff with the same treble and bass clefs used by many non-percussive instruments. Music for percussive instruments without a definite pitch is often notated with a specialist rhythm or percussion-clef; although sometimes a bass clef is simply substituted for rhythm clef.

Classifications

Most percussion instruments have a distinct tone; even a drum can be tuned. However, a distinction is usually made based on whether the instrument can play a definite pitch or not.

The timpani, xylophone, marimba, balafon , vibraphone, bell, tubular bells (chimes in the U.S.A.), crotales and glockenspiel all play a definite pitch. (The piano is often considered a percussion instrument because its sound is created by a hammer striking strings.) The snare drum, bass drum, afuche, various chimes (e.g. mark tree), castanets, claves, cowbell, cymbal, doyra, flexatone, güiro, maracas, mendoza, ratchet, spoons, tambourine, temple blocks, tom-tom, timbales, triangle, vibraslap, washboard, whip and wood block do not in general. However, some percussionists tune drum heads to specific pitches when recording albums or in preparation for specific composer requirements. Gongs and anvils can be tuned or untuned – the most familiar type of gong in the west, the chau gong (sometimes called a tam-tam), is untuned. Tuned cymbals exist but are rare. Often instruments will come in pairs (such as bongos) or larger groups (such as temple blocks); here, there will be a high-low distinction while still retaining indefinite (or unspecified) pitch.

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