Microtonal music can refer to all music which contains intervals smaller than the conventional contemporary Western semitone of 100 cents. The term implies music containing very small intervals but can include any tuning that differs from the western 12-tone equal temperament. The following systems are considered to be microtonal: the traditional Carnatic system of 22 śruti; much Indonesian gamelan music; Thai, Burmese, and African music using seven tones in each (approximate) octave; and blues and/or rock music which makes extensive use of blue notes. Also, music using just intonation, meantone temperament, or other alternative tunings may be considered microtonal
Other terminology has been used (and is still used today) by theorists and composers. Micro-intervals is commonly used to speak about intervals smaller than the semitone, and sometimes macro-intervals for non-multiples of the semitone greater than it. Ivan Wyschnegradsky used the term ultra-chromatic for micro-intervals and infra-chromatic for macro-intervals (Wyschnegradsky 1972, 84-87). Ivor Darreg proposed the term xenharmonic (from the Greek ξένος, foreign, and Greek ξενία, hospitable) for any scale other than the 12-tone equal-tempered scale. (See xenharmonic music).
One reason composers of microtonal music explore alternate tunings is that each unique division of the octave or pseudo-octave creates new interval relationships and thereby new sound possibilities. Just-intonation scales such as Partch's 43 tone unequal scale start with the (non-tempered) diatonic Western scale, and many of them extend it, in Partch's case up to the 11th partial (Partch 1979, 93, 119–37). Some microtonal scales, like the 19 tone or 31 tone equal-tempered scales, contain intervals that are close to those within diatonic scales. Other equal divisions of the octave, such as 15-, 16-, and 17-tone, may also support a diatonic basis for Western musical notation and tonal theory, and have other viable intervallic relationships (Blackwood 1991). For example, although 19-note equal tuning provides the same diatonic chordal relations as are found in 12-note equal tuning, the available chromatic progressions are quite different, because of the closed circle of nineteen fifths, as opposed to twelve. In 12-note equal tuning, a modulating sequence in successive descending minor thirds will return to its starting point at the fourth transposed repetition, but in 19-note tuning the initial chord is not found until the nineteenth transposed repetition, creating a rather confounding but not disagreeable effect (Blackwood 1991, 171).
The earliest music of which a written record exists anywhere on earth appears to be the Hurrian Hymn (Fink 1988; Dumbrill 2000). The clay tablets were discovered in the ancient city of Ugarit on the Mediterranean coast of Syria. The first modern recording of this music was made by Anne Draffkorn Kilmer and Richard L. Crocker in 1976 (Kilmer, Crocker, and Brown 1976). This music may have been microtonal, even though, while interpretation of many aspects of the Hurrian records has been disputed (West 1994), expert opinion overwhelmingly favors some variety of diatonic, Pythagorean tuning (Duchesne-Guillemin 1975, 1977, 1980, 1984; Kilmer 1965, 1971, 1974, 1976; Vitale 1982; West 1994; Wulstan 1968).
The Hellenic civilizations of ancient Greece also left fragmentary records of their music—c.f., the Delphic Hymns. The ancient Greeks approached the creation of different musical intervals and modes by dividing and combining tetrachords, recognizing three genera of tetrachords: the enharmonic, the chromatic, and the diatonic. Ancient Greek intervals were of many different sizes, including microtones. The enharmonic genus in particular featured intervals of a distinctly "microtonal" nature, which were sometimes smaller than 50 cents, less than half of the contemporary Western semitone of 100 cents. In the ancient Greek enharmonic genus, the tetrachord contained a semitone of varying sizes (approximately 100 cents) divided into two such smaller, microtonal, intervals; in conjunction with a larger interval of roughly 400 cents, these intervals comprised the perfect fourth (approximately 498 cents, or the ratio of 4/3 in just intonation) (West 1992, 160–72).
Joel Mandelbaum has argued in his PhD thesis that scholarship done on the Antiphonarium Codex Montpellier suggests that it records microtonal tunings, probably the Greek enharmonic (Mandelbaum 1961). In his opinion, this indicates that microtonal tunings survived and were commonly used late into the medieval period.
Meantone tunings sound similar to, but more harmonious than, the later Western tuning of 12 equal semitones per octave, when performed on an instrument limited to 12 pitches per octave, as long as the music is restricted to a narrow compass of musical keys close to the root note of the tuning (i.e., if the meantone tuning is tuned starting with C, the keys close to C major will sound like a more harmonious take on conventional Western music; distant keys, however, like Eb minor, will contain highly audibly exotic and sometimes discordant musical intervals.) Such extensive modulation in meantone tuning on a 12-note-per octave instrument sounds "wolf" fifths and other exotic musical intervals not found in music using 12 equal pitches per octave.
Many tunings of meantone temperament can be made to close, in practice, using a manageable number of notes per octave. The 1/3-comma and 1/4-comma meantones close very nearly in 19 and 31 tones per octave, respectively, with better approximations to the 5-limit thirds and sixths of the diatonic scale than can be found on modern 12-tone instruments.
Guillaume Costeley's "Chromatic Chanson", Seigneur Dieu ta pitié of 1558 used 1/3 comma meantone and explored the full compass of 19 pitches in the octave, making use of audibly microtonal intervals like the 63-cent interval of 1/19 of an octave (Lindley 2001a).
The Italian Renaissance composer and theorist Nicola Vicentino (1511–1576) experimented with microintervals and built a keyboard with 36 keys to the octave, known as the archicembalo. However Vicentino's experiments were primarily motivated by his research (as he saw it) on the ancient Greek genera, and by his desire to have beatless intervals (when played with near-harmonic-series timbres) available within chromatic compositions.
Jacques Fromental Halévy composed a quarter-tone work for soli, choir and orchestra "Prométhée enchaîné" in 1849, and European composers produced an ever-increasing number of microtonal compositions as the 19th century waned and the 20th century began.Citation needed|date=March 2010
By the 1910s and 1920s, a fad emerged for quarter tones (24edo), inspiring composers as Charles Ives, Julián Carrillo, Alois Hába, Ivan Wyschnegradsky, and Mildred Couper. Such was the popularity of 24 equal during the late teens and 1920s, for example, that Erwin Schulhoff gave classes in quarter-tone composition at the Prague Conservatory.Citation needed|date=March 2010 Béla Bartók came late, and only sporadically, to quartertones (e.g. in his Sonata for violin solo, which uses quarter tones in an essential manner).
Alexander John Ellis, who in the 1880s produced a translation with extensive footnotes and appendices to Helmholtz's On the Sensations of Tone, proposed an elaborate set of exotic just intonation tunings and non-harmonic tunings (Helmholtz 1885, 514–27). Ellis also studied the tunings of non-Western cultures and, in a report to the Royal Society, determined that they did not use either equal divisions of the octave or just intonation intervals (Ellis 1884). Ellis inspired Harry Partch immensely (Partch 1979, vii).
During the Exposition Universelle of 1889, Claude Debussy heard a Balinese gamelan performance and was exposed to their non-Western tunings and rhythms. Some scholars have ascribed Debussy's subsequent innovative use of the whole-tone (6 equal pitches per octave) tuning in such compositions as the Fantaisie for piano and orchestra and the Toccata from the suite Pour le piano to his exposure to the Balinese gamelan at the Paris exposition (Lesure 2001), and have asserted his rebellion at this time "against the rule of equal temperament" and that the gamelan gave him "the confidence to embark (after the 1900 world exhibition) on his fully characteristic mature piano works, with their many bell- and gong-like sonorities and brilliant exploitation of the piano’s natural resonance" (Howat 2001). Still others have argued that Debussy's works like L'Isle joyeuse, La Cathédrale engloutie, Prélude à l'après-midi d'un faune, La Mer, Pagodes, Danseuses de Delphes, and Cloches à travers les feuilles are marked by a more basic interest in the microtonal intervals found between the higher members of the overtone series, under the influence of Hermann Helmholtz's writings (Don 1991, 69 et passim). Berliner's introduction of the phonograph in the 1890s allowed much non-Western music to be recorded and heard by Western composers, further spurring the use of non-12-equal tunings.
While experimenting with his violin in 1895, Julian Carrillo (1875–1965) discovered the sixteenths of tone, i.e., sixteen clearly different sounds between the pitches of G and A emitted by the fourth violin string. He named his discovery Sonido 13 (the thirteenth sound) and wrote on music theory and the physics of music. He invented a simple numerical musical notation that can represent scales based on any division of the octave, like thirds, fourths, quarters, fifths, sixths, sevenths, and so on (even if Carrillo wrote, most of the time, for quarters, eights, and sixteenths combined, the notation is able to represent any imaginable subdivision). He invented new musical instruments, and adapted others to produce microintervals. He composed a large amount of microtonal music and recorded about 30 of his compositions.
Major microtonal composers of the 1920s and 1930s include Alois Hába (quarter tones, or 24 equal pitches per octave, and sixth tones), Julian Carillo (24 equal, 36, 48, 60, 72, and 96 equal pitches to the octave embodied in a series of specially custom-built pianos), Ivan Wyschnegradsky (third tones, quarter tones, sixth tones and twelfth tones, non octaving scales) and the early works of Harry Partch (just intonation using frequencies at ratios of prime integers 3, 5, 7, and 11, their powers, and products of those numbers, from a central frequency of G-196) (Partch 1979, chapt. 8, "Application of the 11 Limit", 119–37).
Prominent microtonal composers or researchers of the 1940s and 1950s include Adriaan Daniel Fokker (31edo), Partch again (continuing to build his handcrafted orchestra of microtonal just intonation instruments) and Ivor Darreg (who built the first fully retunable electronic synthesizer capable of any division of the octave, just or equal or non-just non-equal).
Barbara Benary also formed Gamelan Son of Lion around this period, and Lou Harrison was instrumental in creating American gamelan orchestras at Mills College. In Europe, the "Spectralists" in Paris created their first works from 1973 on with an extensive use of microtonal harmony. The main composers were Hugues Dufourt, Gérard Grisey, Tristan Murail and Michael Levinas; see also the Parisian ensemble "L'itinéraire".
Digital synthesizers from the Yamaha TX81Z (1987) on and inexpensive software synthesizers have contributed to the ease and popularity of exploring microtonal music.
Microtonalism in electronic music
Electronic music facilitates the use of any kind of microtonal tuning, and sidesteps the need to develop new notational systems (Griffiths, Lindley, and Zannos 2001). In 1954, Karlheinz Stockhausen built his electronic Studie II on an 81-step scale starting from 100 Hz with the interval of 5^(1/25) between steps (Stockhausen 1964, 37), and in Gesang der Jünglinge (1955–56) he used various scales, ranging from seven up to sixty equal divisions of the octave (Decroupet and Ungeheuer 1998, 105, 116, 119–21). In 1955, Ernst Krenek used 13 equal-tempered intervals per octave in his Whitsun oratorio, Spiritus intelligentiae, sanctus (Griffiths, Lindley, & Zannos 2001).
In 1986, Wendy Carlos experimented with many microtonal systems including just intonation, using alternate tuning scales she invented for the album Beauty In the Beast. "This whole formal discovery came a few weeks after I had completed the album, Beauty in the Beast, which is wholly in new tunings and timbres" (Carlos 1989–96).
Microtonalism in rock music
A form of microtone known as the blue note is an integral part of rock music and its predecessor, blues. The blue notes, located on the third, fifth, and seventh notes of a diatonic major scale, are flattened by an inexact amount, generally less than a semitone. The flattened fifth is also known as the sharpened fourth (Ferguson 1999, 20).
The band Cipher (Los Angeles-late 70s to mid 80s) played in a 7-limit 22-tone scale of Erv Wilson. The intonation was done under the guidance of Jose Garcia who refretted all the guitars and bass. Co-composer, Marsha Mann, who was the lead singer and lyricist for the band, also sang in the same tuning. They appeared on New Wave Theater. Cipher is listed and pictured (above The Clash) in the 1985 illustrated encyclopedia, 'Who's New Wave in Music', by David Blanco, who refers to them as a 'microtonal dance band'.
Also part of the L.A. punk scene was Kraig Grady who played extensively both as a solo act (on pump organ and hammered dulcimer) and as a member of bands such as the string ensemble Fat and Fucked Up and Brad Laner’s large ensemble Debt of Nature. Grady's instruments were retuned to his 7-limit Centaur tuning.
The Japanese band Syzygys (Hitomi Shimizu and Hiromi Nishida) have released two albums utilizing the 43-tone scale of Harry Partch, using a modified reed organ (Syzygys 2007).
Zia has released several albums making use of the Bohlen–Pierce scale and other equal temperaments such as the 19tet and 10tet. Zia performs on electronic instruments that specifically do not reference the standard 12-tone tuning (ZIA ).
The November 2004 WSES Official Newsletter for Acoustics, Science, and Technology of Music mentions that "bands from Sonic Youth to Art Rock Circus have written music with non-standard and microtonal guitar tunings." Sonic Youth uses alternate tuned guitars with several strings tuned slightly different from each other, creating a beating sound. The third bridge technique led to the microtonal scale used on the Yuri Landman's Moodswinger and his clarification based on this scale about the physical consonant paradox present in experimental rock (Landman 2008). These Are Powers modified their bass guitar into a microtonal adjusted instrument based on the changed musical scale of the bass guitar (Carr 2008). Because the fretboard isn't representing the 12edo anymore because of the preparation, the chord combinations and tone progressions form an altered microtonal spectrum. The Japanese multi-instrumentalist and experimental musical instrument builder Yuichi Onoue developed an 24edo quarter tone tuning on his guitar as well as a deeply scaloped electric guitar for microtonal playing techniques (Landman [n.d.]).
- 3rd Bridge
- Arab tone system and maqam
- Fokker periodicity blocks
- Genus (music)
- Just intonation
- Limit (music)
- MIDI tuning standard
- Music of India
- Musical scale
- Musical tuning
- Partch's 43-tone scale
- Quarter tone
Western microtonal pioneers
Pioneers of modern Western microtonal music include:
- Henry Ward Poole (keyboard designs, 1825–1890)
- Eugène Ysaÿe (Belgium, U.S.A., 1858–1931, used quarter tones in several of the Sonatas for Solo Violin, Op. 27)
- Charles Ives (U.S.A., 1874–1954, quartertones)
- Julián Carrillo (Mexico, 1875–1965) many different equal temperaments, look [http://paginas.tol.itesm.mx/campus/L00280370/carrillo.html here] or [http://paginas.tol.itesm.mx/campus/L00280370/julian.html here] (mostly Spanish but some English too)
- Béla Bartók (Hungary, 1881–1945, rare uses of quartertones)
- George Enescu (Romania, France, 1881–1955) (in Œdipe to suggest the enharmonic genus of ancient Greek music, and in the Third Violin Sonata, as inflections characteristic of Romanian folk music)
- Karol Szymanowski (Poland, 1882–1937, used quartertones on the violin in Myths Op. 30, 1915)
- Percy Grainger (Australia, 1882–1961, particularly works for his "free music machine")
- Edgard Varèse (France, U.S.A., 1883–1965, quartertones)
- Luigi Russolo (Italy, 1885–1947, used quartertones and eighth tones on the Intonarumori, noise instruments)
- Mildred Couper (U.S.A., 1887–1974, quartertones)
- Alois Hába (Czechoslovakia, 1893–1973, quartertones and other equal temperaments)
- Ivan Wyschnegradsky (U.S.S.R. (Russia), France, 1893–1979, quartertones, twelfth tones and other equal temperaments)
- Harry Partch (U.S.A., 1901–1974, just intonation)
- Eivind Groven (Norway, 1901–1977, 53ET)
- Henk Badings (The Netherlands, 1907–1987, 31ET)
- Maurice Ohana (France, 1913–1992, third tones (18-equal) temperament and quarter tones (24ET) most particularly)
- Giacinto Scelsi (Italy, 1905–1988, intuitive linear tone deviations, quartertones, eighth tones)
- Lou Harrison (U.S.A., 1917–2003, just intonation)
- Ivor Darreg (U.S.A., 1917–1994)
- Jean-Etienne Marie (France, 1919–1989, many different equal temperaments: 18ET, 24ET, 30ET, 36ET, 48ET, 96ET most particularly and polymicrotonality)
- Franz Richter Herf (Austria, 1920–1989, 72-equal temperament, "ekmelic" music)
- Iannis Xenakis (Greece, France, 1922–2001, quarter and third tones most particularly, occasionally eighth tones)
- György Ligeti (Hungary, 1923–2006, Ramifications in quartertone tuning, natural harmonics in his Horn Trio, later just intonation in his solo concertos)
- Luigi Nono (Italy, 1924–1990, quartetones, eighth tones and 16th tones)
- Claude Ballif (France, 1924–2004, quartertones)
- Tui St. George Tucker (1924–2004)
- Pierre Boulez (France, b. 1925) (first attempt of serial music with quartertones in his pieces Visage Nuptial and "Polyphonie X", but soon after abandoning microtonal elements)
- Karlheinz Stockhausen (Germany, 1928–2007, in his electronic works many microtonal concepts, non-octaving scales in Studie II, just intonation in Gruppen and Stimmung, microtonal instrumental and vocal writing throughout Licht)
- Ben Johnston (U.S.A., b. 1926, extended just intonation)
- Ezra Sims (U.S.A., b. 1928, 72-tone equal temperament)
- Erv Wilson (b. 1928)
- Alvin Lucier (U.S.A., b. 1931)
- Joel Mandelbaum (U.S.A., b. 1932)
- Krzysztof Penderecki (Poland, b. 1933, quartertones)
- Easley Blackwood (b. 1933)
- Alain Bancquart(France, b.1934) (quarter tones and 16th tones)
- James Tenney (U.S.A., 1934–2006, just intonation, 72-tone equal temperament)
- Terry Riley (U.S.A., b. 1935, just intonation)
- La Monte Young (U.S.A., b. 1935, just intonation)
- Douglas Leedy (b. 1938, just intonation, meantone)
- Wendy Carlos (U.S.A., b. 1939, non-octaving scales)
- Bruce Mather (Canada, b.1939, different equal temperaments, following Wyschnegradsky)
- Brian Ferneyhough (Great Britain, b. 1943, quartertones, 31ET in Unity Capsule for solo flute,1976)
Recent microtonal composers
- Clarence Barlow (b. 1945)
- Gérard Grisey (1946–1998) (spectral approach to microintervals, quartertones, eighth tones)
- Max Méreaux (b. 1946)
- Tristan Murail (b. 1947) (spectral approach to microintervals, quartertones, eighth tones)
- Claude Vivier (1948–1983)
- Glenn Branca (b. 1948)
- Dean Drummond (b. 1949) (Harry Partch's instruments currently in his possession)
- Lasse Thoresen (b. 1949)
- Warren Burt (b. 1949)
- Manfred Stahnke (b. 1951)
- Kraig Grady (b. 1952) (invented acoustic instruments in just intonation & recurrent sequences)
- David First (b. 1953)
- Georg Friedrich Haas (b. 1953)
- James Wood (b. 1953)
- Paul Dirmeikis (b.1954)
- Pascale Criton (b. 1954) (different equal temperaments, most particularly very dense ETs such as the 96ET)
- Stephen James Taylor (b. 1954)
- Kyle Gann (b. 1955)
- Pascal Dusapin (b. 1955) (different equal temperaments, notably the 48ET)
- Johnny Reinhard (b. 1956) (different equal temperaments, just intonation, polymicrotonally)
- Eric Mandat (b. 1957)
- Erling Wold (b. 1958)
- Michael Bach Bachtischa (b. 1958)
- Martin Smolka (b. 1959)
- Georg Hajdu (b. 1960)
- William Susman (b. 1960)
- Daniel James Wolf (b. 1961)
- François Paris (b.1961)
- Rod Poole (b.1962 - d.2007)
- Harold Fortuin (b. 1964)
- Marc Sabat (b. 1965)
- Georges Lentz (b. 1965)
- Geoff Smith (b. 1966)
- Yitzhak Yedid (b.1971)
- Richard D. James (b. 1971)
- Adam Silverman (b. 1973)
- Yuri Landman (b. 1973)
- Kristoffer Zegers (b. 1973)
- Gregg Rossetti (b. 1982)
- Christiaan Huygens (1629–1695)
- Julián Carrillo (1875–1965)
- Adriaan Daniël Fokker (1887–1972)
- Ivan Wyschnegradsky (1893–1979)
- Alois Hába (1893–1973)
- Harry Partch (1901–1974)
- Alain Daniélou (1907–1994)
- Jean-Etienne Marie (1917–1989)
- Erv Wilson (b. 1928)
- Joel Mandelbaum (b. 1932)
- James Tenney (1934–2006)
- Clarence Barlow (b. 1945)
- Valeri Brainin (b. 1948)
- Jacques Dudon (b. 1951)
- William Sethares (b. 1955)
- Georg Hajdu (b. 1960)
- Bob Gilmore (b. 1961)
- Marc Sabat (b. 1965)
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- [[[MicrotonalListeningList|http://xenharmonic.wikispaces.com/MicrotonalListeningList]] Links to microtonal composers] at Xenharmonic Wiki
- [[[Projects|http://xenharmonic.wikispaces.com/Projects]] Links to microtonal projects around the world] at Xenharmonic Wiki