Aug 132017

A brief compilation of definitions, perspectives and practices on the topic of xenharmonic music…

From Wikipedia, the free encyclopedia

Ivor Darreg

He coined the term “xenharmonic”, designed and built many original microtonal musical instruments, and wrote voluminous amounts of material about various musical tunings. Perhaps his most important contribution to music theory was his idea that different tunings exhibit different “moods”.

From Wikipedia, the free encyclopedia

Xenharmonic Music

Xenharmonic music is that which uses a tuning system which neither conforms to nor closely approximates the common 12-tone equal temperament. The term xenharmonic was coined by Ivor Darreg, from xenia (Greek ξενία), “hospitable,” and xenos (Greek ξένος) “foreign.” He stated it as being “intended to include just intonation and such temperaments as the 5-,7-, and 11-tone, along with the higher-numbered really-microtonal systems as far as one wishes to go.”

John Chalmers, author of “Divisions of the Tetrachord”, writes: “The converse of this definition is that music which can be performed in 12-tone equal temperament without significant loss of its identity is not truly microtonal.” Thus xenharmonic music may be distinguished from the more common twelve-tone equal temperament, as well as some use of just intonation and equal temperaments, by the use of unfamiliar intervals, harmonies, and timbres.

Elaine Walker | NewMusicBox

What Is Xenharmonic Music?

“Xenharmonic” is the generic term that we use to refer to scales that have more, or less, notes per octave than our standard twelve-tone tuning. The pitches in xenharmonic scales are either too close together or too far apart to fit any familiar melody we’ve ever known. However, it is possible to write new music with new harmonic relationships that humankind has never heard before.

Elaine Walker is an electronic musician, microtonal composer, and builds new types of music keyboards. She is also the author of a physics/philosophy book, Matter Over Mind: Cosmos, Chaos, and Curiosity.

Xenharmonic Music Introduction and Tutorial | Brendan Byrnes

Introduction to xenharmonic/microtonal music concepts, tuning, and the harmonic series. Analysis of “Kaleidoscopic”. Music and tutorial by Brendan Byrnes.

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 Posted by at 1:50 pm
Jul 222017

Former Korg engineer, Tatsuya Takahashi’s Monologue, featuring full-keyboard microtuning (Scala SCL/MTS formats)

Of potential interest to microtonal music and technology enthusiasts, is a recent discussion, in the form of an interview published on the Warp Records’, Item, section of their site, between Richard D. James (aka Aphex Twin) and Tatsuya Takahashi (former Korg engineer of the microtunable Monologue, now advisor).

ITEM • Richard D. James speaks to Tatsuya Takahashi

In many ways, this is the Aphex Twin interview I’ve been hoping to read for some time, because one of the central topics discussed here are music technologies that feature full-keyboard microtuning and his approach to the topic. It was also very interesting to learn from this article the influence that RDJ had on the microtuning implementation of the Korg Monologue.

Like lots of colleagues involved in the field of xenharmonic and microtonal music, I first became aware of Aphex Twin’s use of microtunings on his seminal record, Selected Ambient Works Vol. II (1994), so it’s extremely fascinating to get some deeper details about his methods, and in particular his use of Manuel Op de Coul’s excellent Scala, the freeware microtuning application we all know and love, and which happens to be a topic of frequent focus on the pages of Xen-Arts. Clearly microtuning is a central feature of his work, as its use is evident as well on the recent record, AFX ‎– London 03.06.17, also on Warp Records (WAP400).

I thought the comment in the article about hardware FM synths lacking filters was very interesting (although some astute readers will be aware that the Yamaha SY series had them), and having owned a couple of Yamaha TX81Zs and a TX802 back in the day, it’s something I have long ago found deep resonance with, and have only been able to address the issue on a personal level with the custom-built microtonal FM VSTi on offer here at Xen-Arts, that not only feature filters, but which importantly, can also be audio-rate modulated with high-precision partials-file controlled oscillator sources, an application which can be used for generating microtuning related sideband spectra were needed. It’s a synthesis technique of great utility really.

The likelihood of seeing this type of spectral-microtuning audio-rate modulated filters design on a modern hardware FM synth would seem highly improbable in our 12-locked technological times, although on the other hand, it’s extremely exciting to see any kind of hardware based full-keyboard microtuning implementation taking shape these days, such as in the case of the great Dave Smith Instruments line (MTS), and the above discussed Korg Monologue (also MTS capable).

From Synthtopia:

Korg Monologue Intro, With Chief Engineer Tatsuya Takahashi

Aphex Twin Site:

Aphex Twin

Scala by Manuel Op de Coul:


 Posted by at 12:44 pm
Jul 162017

Xen-Arts is extremely pleased to present here the first in what will be a future series of Xen-Artist Showcase articles that will endeavor to feature, celebrate, acknowledge and highlight the work of individuals and groups working in the field of microtonal and xenharmonic music, including, but not necessarily limited to composers, musicians and music technology developers that might be of potential interest to visitors and readers of this site from around the world.

First up in our Xen-Artist Showcase is a feature about the work and music of Brazilian-born orchestral conductor, multi-instrumentalist and microtonal music composer, Fabio Costa, currently residing in the creative centers of Berlin Germany, including a generous and illuminating interview with the composer himself.

Fabio Costa | Xen-Artist Showcase 01

Microtonal Music Background and Intonation Preferences

Xen-Arts: It would be very interesting to learn about your formative discoveries and experiences with exploring alternative intonation systems (temperaments, just-intonation, non-octave, historical, traditional, etc.).  How did you first become aware of musical instrument intonation systems outside of the ubiquitous Western 12-tone-equal-temperament, and what were some of the early inspirations and factors that led to you actively composing music with them, if indeed they were not already a facet of your cultural experience, musical training and traditional background? What were some of the categories of intonation systems that were of initial interest to you in those formative times, as well as those that are now at the center of your current practice and research?

If being able to freely modulate through many possible – and harmonically stable – tonal centers of a microtuning system is important to your compositional style(s), please discuss how this informed your current intonation choices.

Do the requirements of your compositional style(s) require that you have a complete, densely microtonal gamut (microchromatic: J. Ligon, polychromatic: D. Catherino) tuning system mapped to your instrument(s) at all times, or do you tend to switch freely between intonation systems that may feature arbitrary numbers of tones or theoretical structures?

Fabio Costa: I believe the main experiences that primed me for xenharmony were on the one hand an exposure to the original performance movement of old (baroque & renaissance) music and on the other hand, I have played the oboe between ages 17 and 25 also professionally in orchestras, which soon made me aware of the tuning issues within the 12-ED2, mainly regarding the (major) 3rds in chords (in a woodwind section in the orchestra for instance). I have received have a decent education in foundations of mathematics and my curiosity drew me more and more to the overtone series and the harmonic implications thereof. At the same time, some compositions of mine in 12-ED2, for instance, my Prelude-Meditation for Organ:

…employed tonal cadences that I only later would identify as approximations of higher-limit natural intervals of the overtone series, such as 7:9:11 . With the tools I had at hand, I transcribed that piece into 19-limit just intonation, moved by the curiosity of how it would sound. I wasn’t aware at the time (2009) that other equal temperaments existed, which could approximate those intervals. That only happened in late 2014 through a composer colleague that made me aware of that. Since then I started delving deeper into this area, also leading to a collaboration with the Huygens-Fokker Foundation in Amsterdam, which houses the 31-ED2 organ built by Adriaan Fokker in the 1950s and organizes a musical life around it.

My particular compositional interest goes toward the possibilities presented by higher harmonic limits and of enharmony, which of course is related to equal divisions of the octave.

Microtonal Music Practice and Performance Experiences

Xen-Arts: Obviously, there is a period of acclimation in hearing, composing and performing in non-ED2-12 systems. Could you illuminate what have been your experiences regarding the willingness and enthusiasm of performers in embracing both the rigors of accurately rendering the intervals of particular intonation systems, as well as the notation systems used to convey the intervals, melodic and harmonic forms in a particular compositional scenario?

Fabio Costa: My experiences were above all with 31-ED2 together with musicians around the Huygens-Fokker Foundation, which have a solid background in renaissance and baroque music and also in part some experience with 31, but even those who have not seem to transition very intuitively to 31 notes, which I believe is given through the familiarity of 31 with meantonal tunings of renaissance/baroque but also through some intuitive feeling of harmonic relations that 5 limit performance in J.I. develops.

One important aspect in my view is the possibility to actually perform with musicians, who inevitably will come from a 12-ED2 background, so I think one has to find a compromise between good sound and the complexity of many notes (such as 41 or 53), especially maintaining a reference to traditional 12 notes. In this sense I believe adaptive systems are the best practical way to go in that particular context, for instance using 24-ED2 and correcting the “bad” intervals of it (7, 5 etc) in performance. This was very effectively done for instance by my colleague composer Sander Germanus with musicians from Calefax & DoelenEnsembles:

…or with 4-tone pianos:

Of course a purely electronic medium does not impose that limitation.

Instrument Preferences

Xen-Arts: Acoustic, classical, or orchestral music experiences with alternative intonation systems, including insights and visions for the future? Your instruments of preference, both ED2-12 and microtonal? What features might embody your dream-controller(s) for rendering microtonal and xenharmonic music compositions, embracing without bias, acoustic, electronic, computer-music, or MIDI oriented instruments of any kind?

Fabio Costa: I am fascinated by all “error” elements that make up real sound by physical instruments, such as noise in the first place, but also the various inharmonicities and irregularities (of partials for instance), which help dilute the errors/imperfections of the systems based on equal divisions of 2:1 themselves. For instance the Organ, that has much noise and turbulence, makes a complex harmonic web, such in the final section of my Aphoristic Madrigal:

…sound surprisingly “just”, considering that many errors of 31 are not at all negligible (10 cents) and become very apparent with relatively simple electronic sounds.

Xen-Arts: Yes – I agree. Your ED2-31 composition is not only exquisitely beautiful to my ears, but for all practical purposes, virtually ‘just’ sounding. The sensation is as if I’m hearing a section of the harmonic series rendering the harmony here, and the organ with its timbral noise component lends an organic and ‘breathing’ quality to the composition. The performance and impeccable intonation of the singers is spectacular as well. Excellent work!

I was also equally impressed by your “…and while there he sighs…” for the 31-tone Fokker-Organ:

Fabio Costa: Another good example for this relation between tuning system and physical medium is the piano, of which the stretched overtone series compensates for the very sharp major third and makes 12-ED2 sound good on it; I believe this was one of the main factors of this system becoming the standard in a 19 century dominated by piano music. In fact, I think the piano sounds less well in just-intervals, out of that same reason.

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 Posted by at 8:12 pm