Twelve-tone technique

Twelve-tone technique (also dodecaphony and, especially in British usage, twelve-note composition) is a method of musical composition devised by Arnold Schoenberg. The technique is a means of ensuring that all 12 notes of the chromatic scale are sounded as often as one another in a piece of music. All 12 notes are thus given more or less equal importance, and the music avoids being in a key. The technique was tremendously influential on composers in the mid-20th century.
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