Microtonal Music

Microtonal music uses intervals smaller than the equal-tempered semitone — quarter tones, cent-precise just-intonation ratios, scales of forty-three or seventy-two notes per octave. Composers approach it from many angles. Harry Partch rejected twelve-tone equal temperament entirely and built a forty-three-tone-per-octave instrument family from scratch; his 'Castor and Pollux' (1952) uses those instruments to produce a music that sounds 'off' until the ear adjusts. Gyorgy Ligeti's 'Lontano' (1967) is played on standard orchestral instruments but instructs string players to hold slightly different pitches, producing audible beating and a blurred mass.

Alois Haba in Prague built quarter-tone pianos in the 1920s. Julian Carrillo in Mexico worked with sixteenth-tone divisions in roughly the same period. Harry Partch began his work in the 1930s and continued for the rest of his life. The French spectralists (Gerard Grisey, Tristan Murail) in the 1970s arrived at microtonality through the harmonic series rather than equal-step divisions, treating microtones as 'natural' harmonics of a low fundamental.

Ben Johnston's 'String Quartet No. 4' (1973) keeps the format of a string quartet but tunes the parts to extended just intonation; the beating between not-quite-matching pitches is the texture. In Ligeti's 'Lontano', no individual instrument plays a 'microtonal' instrument, but the collective is detuned enough that the orchestral mass loses its focus.

Ligeti's 'Lontano' (1967) is the most accessible entry because the instruments are familiar. Harry Partch's 'Castor and Pollux' (1952) shows the full custom-instrument approach. Read a short note on the tuning before listening — the theory makes the experience legible.

Partch's instruments — the Cloud Chamber Bowls, the Chromelodeon, the Bass Marimba — are preserved at the University of Washington and remain playable. La Monte Young's drone-based work in just intonation is a parallel American thread that overlaps with this lineage.