This is the first in a series of conversations with composers who work in just intonation, and other microtonal systems. Questions from Ekmeles are bolded, the composer’s responses follow.
Why not 12-note equal temperament?
It comes down to this question, one I ask myself often: What exactly enchants me as a listener in the music I love? More often than not, it’s small expressive details that capture my attention, the fleeting surface gestures or stylistic inflections that make a performance distinctive. Replicating that kind of expressivity requires a full palette of pitch material; my works often run the gamut, mixing highly-detailed microtonality with tempered passages. Microtones are a vital component of almost every musical tradition: jazz, blues, country, electronic music, many folk styles, early music — almost everywhere except in the mainstream art music of the last few centuries.
Speaking more broadly, I’m captivated by the idea of consonance, and devoted to pushing the boundaries of what can be considered to “sound good.” Just intonation sparks my imagination because what appears to be a complex network of pitch relationships can be boiled down to multiples of whole numbers, simplest ratios that require extreme precision in tuning. I’m very attracted to this idea that simplicity and complexity can be a matter of perspective.
Why the systems and pitches you use?
My approach is simple: the system has to fit the project. I’m very concerned with making my music practical form a performance standpoint, so that the microtones can be reliably performed — whatever that might mean in a given context. I’ve often used the trick of retuning winds, plucked strings (guitar, mandolin, autoharp), or bowed strings (playing only harmonics and open strings) down by a quarter-tone, so that a player can use “normal” fingerings but still play reliable microtones.
I’ve also written for instruments which are specifically designed to produce microtones, in which case the system is more or less decided for me. I’ve worked extensively with the qanûn for instance, a middle-eastern zither equipped with small levers under the string that can produce microtones by changing the string length. I’ve used both the Syrian version (in Üsküdar and Widening Circles) which gives tempered quarter-tones, as well as a just intonation qanûn designed by Julien Weiss, for whom I wrote a solo part tailored to his particular tuning system in Cognitive Consonance. Or another example: the Fokker Organ, a MIDI-controlled microtonal organ in the Amsterdam Muziekgebouw, for which I also composed a short piece.
Another approach I’ve used is to write strictly tempered music for tempered instruments complemented by electronically created microtonal sounds, aiming for a fusion of live sound and synthesis or retuned samples that sounds like a single microtonal instrument. And there’s also my hexaphonic electric guitar, whose strings can be electronically retuned by a Max/MSP patch. I find that working with electronics offers the broadest range of possibility and precision, and a lot of my most fantastical pitch-related ideas are best realized in that medium.

A qanûn, showing the levers used for tuning
What was your first encounter with microtones?
Wow, it’s coming up on a decade now… Shortly after I first moved to Paris in 2003, I caught a complete performance of Gérard Grisey’s Les Espaces Acoustiques. I’d heard Partiels (the third piece in the series) about a year earlier, and (weird to think of this in retrospect) only the theatrics at the end made an impression. But being enveloped by those lush harmonies in the concert hall was life-changing. Microtones were the key, it dawned on me around then, and I started devouring all the French microtonal music I could find, starting with Murail, Hurel, Leroux… For my first piece with microtones — a quartet for four clarinets written in 2004 — I decided I’d consciously train myself to hear microtonal intervals, and started constructing chords from slices of the harmonic series. But even in this first piece, I wasn’t doing just intonation drones, but working towards a richer polyphony, focusing on the voice-leading interactions between multiple microtonal lines.
My second microtonal revelation came when I discovered Turkish music. Often you hear that microtonal music has to be slow to be effective, that it takes the ear a while to attune itself to “unfamiliar” intervals. But in Ottoman classical music I discovered an entire tradition of fast and yet extremely precise microtones. The Turks rely on a combination of specially designed instruments and an internalized tradition that divides the octave (approximately but not quite exactly or consistently) into 53 parts. The idea that a microtonal theoretical framework could exist in tandem with a practice that tolerations deviations (which is in fact the way most supposedly tempered music is performed!) was illuminating for me and a source of inspiration for several pieces to follow.

Excerpt from Trapani’s Cognitive Consonance
What piece of microtonal music that you didn’t write is most important to you?
I’ll go with either Harry Partch’s And on the Seventh Day the Petals Fell in Petaluma or Blind Willie Johnson’s version of “Dark was the Night, Cold was the Ground”