Tone row

In music, a tone row or note row (German: Reihe or Tonreihe), also series and set, refers to a non-repetitive ordering of a set of pitch-classes, typically of the twelve notes in musical set theory of the chromatic scale, though both larger and smaller sets are sometimes found.

Tone rows are the basis of Arnold Schoenberg's twelve-tone technique and most types of serial music. Tone rows were widely used in 20th-century contemporary music, e.g. Shostakovich's use of twelve-tone rows, "without dodecaphonic transformations", though one has been identified in the A minor prelude from book II of The Well-Tempered Clavier (1742) by J. S. Bach, and by the late eighteenth century was a well-established technique, found in works such as Mozart's C major String Quartet, K. 157 (1772), String Quartet in E-flat major, K. 428, String Quintet in G minor, K. 516 (1790), and the Symphony in G minor, K. 550 (1788).Beethoven also used the technique but, on the whole, "Mozart seems to have employed serial technique far more often than Beethoven".Hans Keller claims that Schoenberg was aware of this serial practice in the classical period, and that "Schoenberg repressed his knowledge of classical serialism because it would have injured his narcissism." There are also examples in the works of Liszt.

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