Microtonality

Microtonal music or microtonality is the use in music of microtones—intervals smaller than a semitone, which are also called "microintervals". It may also be extended to include any music using intervals not found in the customary Western tuning of twelve equal intervals per octave.

Microtonal music can refer to any music containing microtones, therefore it is important to comprehend what a "microtone" is. The words "microtone" and "microtonal" were coined before 1912 by Maud MacCarthy Mann in order to avoid the misnomer "quarter tone" when speaking of the srutis of Indian music (Mann 1912, 44). Prior to this time the term "quarter tone" was used, confusingly, not only for an interval actually half the size of a semitone, but also for all intervals (considerably) smaller than a semitone (Ellis 1877, 665; Meyer 1903). It may have been even slightly earlier, perhaps as early as 1895, that the Mexican composer Julián Carrillo, writing in Spanish or French, coined the terms microtono/micro-ton and microtonalismo/micro-tonalité (Donval 2006, 119).

In French, the usual term is the somewhat more self-explanatory micro-intervalle, and French sources give the equivalent German and English terms as Mikrointervall (or Kleinintervall) and micro interval (or microtone), respectively (Amy 1961; Anon. 1998; Wallon 1980, 13; Whitfield 1989, 13. "Microinterval" is a frequent alternative in English, especially in translations of writings by French authors and in discussion of music by French composers (Battier and Lacino 1984, 79; Boulez 1958, 22–23; Rae 2013, 164, 174n40). In English, the two terms "microtone" and "microinterval" are synonymous (Maclagan 2009, 109). The English analogue of the related French term, micro-intervallité, however is rare or nonexistent, normally being translated as "microtonality"; in French, the terms micro-ton, microtonal (or micro-tonal), and microtonalité are also sometimes used, occasionally mixed in the same passage with micro-intervalle and micro-intervalité (Donval 2006, 119, 183; Jedrzejewski 2014, passim; Rigoni 1998, 314).

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