Microtonality

${ \new Staff \with{ \magnifyStaff #2 \omit Score.TimeSignature } { \fixed c' <c disih g aisih>1 } }$

Composer Charles Ives chose the chord above as a good candidate for a "fundamental" chord in the quarter tone scale, akin not to the tonic but to the major chord of traditional tonality^[1]

Two examples of an Ives fundamental chord with quarter tones

Microtonality is the use in music of microtones — intervals smaller than a semitone, 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. In other words, a microtone may be thought of as a note that falls "between the keys" of a piano tuned in equal temperament.

^ Boatwright, Howard (1971). "Ives' Quarter-Tone Impressions". In Boretz, Benjamin; Cone, Edward T. (eds.). Perspectives on American Composers. Princeton: Princeton University Press. pp. 8–9. ISBN 978-0-393-02155-4.

[1] Boatwright, Howard (1971). "Ives' Quarter-Tone Impressions". In Boretz, Benjamin; Cone, Edward T. (eds.). Perspectives on American Composers. Princeton: Princeton University Press. pp. 8–9. ISBN 978-0-393-02155-4.

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