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  • Seth Hahn

Julian Carillo

Julian Carrillo-- who exactly is he? While not as well known of a composer as someone like Beethoven, Bach, or Mozart, Mexian composer Julian Carrillo was still an affluent composer of the modern era. His primary contributions to the classical music world include his development of microtonal music, or music that uses 12 more notes than usual.

Carrillo was born in Ahualulco, Mexico in January of 1875, the nineteenth child out of nineteen children. He began his career in music in his youth, playing violin, singing in church choir, and composing for church choir. As a young adult, he attended National Conservatory of Music in Mexico City, where he studied violin with Pedro Manzano, composition with Melesio Morales, and acoustics with Fransisco Ortega y Fonseca. It was during his studies here that he began his plunge into the world of microtonality, as he concluded that the human ear could differentiate intervals as small one sixteenth of a whole tone. For context, one regular half step is one key apart, like C to C#, which in intervallic terms is called a minor second. Carrillo wanted to access the sounds in between those two keys, creating intervals smaller than a minor second. He envisioned the potential use of four hundred different notes as compared to the standard twelve tone system.

We normally use a system called twelve tone equal temperament, a practice where we divide an octave into twelve pieces. This gives us the twelves note chromatic scale we’re used to, that chromatic scale being C, C#, D, D#, E, F, F#, G, G#, A, A#, and B. In this system, a whole tone, or whole step, is split into two, like how a whole step from C to D split in half creates C#. But in microtonal music, the octave can be split into even smaller parts, creating chromatic scales with larger amounts of notes in them. For example, if we split a whole step into fourths, we get what are called quarter tones. A whole step from C to D split into quarter tones would create the notes C half sharp, C#, and D half flat. Another way to think about it is thinking of an octave as a clock-- twelve o’clock is C, one o’clock is C#, two o’clock is D, all the way to eleven o’clock which is B. A whole tone in the clock example is two hours apart, like C to D, which makes a semitone one hour apart, like C to C#. Quarter tones would be halfway between the hour, like where the hour hand would be at the half hour mark-- C half sharp would be twelve-thirty, D half flat would be one-thirty.

Carrillo envisioned music where a whole tone was split into thirds, fourths, and so on until it was split into sixteenth tones. He dubbed this concept, the “Thirteen Sound Theory,” or “Sonido 13.” He sought to create an array of new pianos, pianos that use different microtonals systems of third tones, quarter tones, fifth tones, and so on through sixteenth tones. Carrillo’s work wasn’t limited exclusively to microtonal music as he composed many musical works in standard twelve tone equal temperament. For example, Three of his six symphonies are microtonal with the other three in twelve tone equal temperament.

Carrillo continued to develop and share Sonido 13, particularly in his home country of Mexico where he gave conferences on his theory. Carrillo’s theory began to gain traction in the music community, as he began receiving commissions in the nineteen-twenties to compose microtonal music, including Maestro Leopold Stokowski, who premiered Carrillo’s new microtonal concertino with the Philadelphia Orchestra. His home country even honored him for his musical advancements, going as far as to declare July 13th as a State Day of Honor for him, as well as raising the Mexican flag over Carrillo’s home for a day.

While not an extremely well known composer, Julian Carrillo was an innovative musician who’s work in microtonal music sets him apart as one of Mexico’s greatest composers.

Work Cited:

Britannica, The Editors of Encyclopaedia. "Julián Carrillo". Encyclopedia Britannica, 24 Jan. 2021, Accessed 10 August 2021

Wikipedia. “Julián Carrillo.” Wikipedia, Wikimedia Foundation, 25 June 2021,

Huygens-Fokker Foundation. “Julian Carrillo.” Huygens-Fokker Foundation,


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