* Pitch: The frequency of a sound wave, measured in hertz (Hz).
* Duration: The length of time a sound lasts, measured in seconds.
* Timbre: The quality of a sound, determined by its overtones.
* Loudness: The intensity of a sound, measured in decibels (dB).
In Tetra music, these four elements are used to create musical compositions that are characterized by their use of repetition, symmetry, and contrast. Tetra music can be composed for any instrument or group of instruments, and can be used in a variety of genres, from classical to electronic music.
Some of the most famous Tetra music compositions include:
* "Tetramusic I" (1975), for four clarinets
* "Tetramusic II" (1976), for four violins
* "Tetramusic III" (1977), for four cellos
* "Tetramusic IV" (1978), for four double basses
* "Tetramusic V" (1979), for four pianos
Tetra music has been praised for its originality and its ability to create music that is both beautiful and complex. It has been performed by some of the world's most famous musicians, including the Kronos Quartet, the Arditti Quartet, and the London Symphony Orchestra.