Microtonalism. Compositional approach employing, either incidentally or systematically, intervals smaller than the semitone of Western tempered tuning. Although microtonalism was explored theoretically in ancient Greece and found practical application in the arcicembalo of the Italian renaissance theorist and composer Nicola Vicentino, it was not widely exploited until the early 20th century, especially in the work of the Czech composer Alois Hába (1893-1973), whose pupils included Karel Ančerl and Walter Susskind, and the Russian-born composer Ivan Wyschnegradsky (1893-1979), who lived in Paris from 1920 until his death. Though not as pervasive as the advances in rhythm and timbre which have characterized 20th-century music, the utilization of micro-divisions of pitch has proved an effective and valid device offering fresh melodic and harmonic expression.
In Canada, the incidental (though of course deliberate) incorporation of microtones arises in passages for voice by Somers (12 Miniatures, 1964) and Schafer (Miniwanka, 1971); in the bending of pitches by wind instruments in works by Aitken, Saint-Marcoux, and others; in gamelan evocations, and pieces emphasizing percussion, by Aitken, Garant, Tremblay, and Vivier; and in such string examples as the unison glides in the finale of Schafer's String Quartet No. 3 (1981). An early microtonal study of the more systematic type is Behrens' Quartertone Quartet (1960). Guest appearances with Canadian new-music ensembles by such microtonal specialists as Lou Harrison and Ben Johnston, starting in the early 1970s, have been influential.
But microtonalism takes on central importance in the work of two composers in Canada - Bruce Mather and James Tenney. During a visit to Paris in 1974, Mather met Wyschnegradsky; deeply impressed with his music, Mather, with Pierrette LePage, arranged to perform and record a selection of it, including several unpublished works. On Wyschnegradsky's death, Mather was asked to prepare an edition of his scores. These experiences left their mark on Mather's own compositions, most of which from the late 1970s on have systematically employed microtonalism. Examples are the chamber works Ausone (1979) for two instrumental ensembles tuned a quarter-tone apart; Barbaresco (1984) for viola, cello, and contrabass; and Poème du délire (1982) for three pianos tuned in sixth-tones.
Tenney too was attracted to novel considerations of pitch, often including microtones, through contact with an older specialist: before emigrating to Canada, he was associated with the US composer Harry Partch (1901-74) as a performing member of Partch's Gate Five ensemble. Beginning in the 1970s, he experimented and wrote theoretical papers on tuning problems, as well as composing such thoroughgoing examples of the approach as Koan (1984), in which just tuning (rather than tempered) results in exact pitch distinctions as small as one-sixth of a semitone.
The theoretical basis for microtonal systems based on non-tempered tuning systems has been explored in detail by the Canadian musicologist Paul Rapoport, who has demonstrated a wide variety of octave subdivisions on the advanced Scalatron electronic keyboard instrument at McMaster University. Tuning systems employing narrow intervals are quite easily attainable with modern computer-assisted music technology, and some Canadian composers (eg, Paul Dolden) have systematically experimented with microtonalism in the medium of electroacoustic music.
Microtonal steps are heard in traditional, popular, and most non-Western musical systems (the inflections of North American blues singing are often cited), and the absorption of elements of these repertoires by many composers, together with the proliferation of sophisticated but relatively inexpensive music technology, may well be indications that microtonalism will continue to be explored by increasing numbers of musicians.