twelve-tone technique

12-tone technique—also known as dodecaphony, twelve-tone serialism, and (in British usage) twelve-note composition—is a method of musicalcomposition devised by Austrian composer Arnold Schoenberg (1874–1951). 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 while preventing the emphasis of any one note^[3] through the use of tone rows, an ordering of the 12 pitches. All 12 notes are thus given more or less equal importance, and the music avoids being in a key. The technique was influential on composers in the mid-20th century.

Schoenberg himself described the system as a "Method of Composing with Twelve Tones Which are Related Only with One Another".^[4] However, the common English usage is to describe the method as a form of serialism.

Schoenberg's countryman and contemporary Josef Matthias Hauer also developed a similar system using unordered hexachords or tropes—but with no connection to Schoenberg's twelve-tone technique. Other composers have created systematic use of the chromatic scale, but Schoenberg's method is considered to be historically and aesthetically most significant.