The Arel-Ezgi-Uzdilek System: Codifying Turkish Makam Theory

Turkish makam music was, for most of its history, a tradition transmitted from teacher to student by ear, with no single written notation and no fixed numerical standard for its microtonal intervals. The Arel-Ezgi-Uzdilek (AEU) system, formalized across the first half of the 20th century, changed that: it gave Turkish makam theory a closed, mathematically justified 53-tone framework that could be printed, taught in a classroom, and cited the way Western theory cites 12-tone equal temperament. It remains the standard taught in Turkish conservatories today — and it has been argued over for nearly as long as it has existed.

An oral tradition meets a new state

Attested Ottoman classical music was traditionally passed down through meşk — direct, repeated, ear-based instruction from master to student. Cem Behar's study of this pedagogical system describes a transmission method built on personal relationship and repetition rather than written text. Attested By the late 19th century this posed a practical problem for reform-minded musicians: without notation precise enough to capture the tradition's microtonal intervals, repertoire could be lost between generations, and Turkish music had no vocabulary for describing itself in the comparative, quasi-scientific terms then being applied to Western music theory.

Attested Rauf Yekta Bey (1871–1935), a Mevlevi neyzen (ney player) and largely self-taught musicologist, made the first systematic attempt at a solution. His 1922 chapter on Turkish music for Albert Lavignac's French Encyclopédie de la musique, citing some 73 notated examples, was the first extensive account of Turkish makam theory published in a Western language, and it introduced a modified staff notation with extra accidentals for microtonal inflections. Attested During the early Republic's conservatory reforms, a repertoire-documentation committee under Yekta's leadership — formalized in 1926 as the Alaturka Mûsıkî Tasnif ve Tesbit Heyeti — worked to notate existing repertoire in the very years a separate reorganization removed Turkish classical music instruction from that same conservatory's curriculum. Standardized, teachable notation had become urgent for reasons well beyond scholarship.

Three successors, one system

Attested The system that carries Arel, Ezgi, and Uzdilek's initials was built on Yekta's foundation over the following decades — refined by each of the three in turn, not published as one joint treatise. Hüseyin Sadettin Arel (1880–1955) trained in law and spent nearly two decades in judicial and legal posts before turning to music theory full-time; he wrote the systematic Türk Musikisi Nazariyatı Dersleri (Lessons in Turkish Music Theory) and, from 1943, headed Istanbul's municipal conservatory — a post that let him institutionalize his own framework directly. Suphi Ezgi (1869–1962), a military physician, undertook the enormous documentary labor behind the system: his five-volume Nazarî ve Amelî Türk Musikisi (Theoretical and Practical Turkish Music) transcribed and analyzed hundreds of existing pieces. Salih Murat Uzdilek (1891–1967), a physics professor, supplied what the other two could not: a rigorous acoustic argument, published in 1944, for why dividing the octave into 53 equal parts approximates Pythagorean, stacked-fifth tuning so closely.

Fifty-three commas, twenty-four tones

Established The mathematics behind the 53-comma division — why 53 stacked fifths nearly close the circle of fifths, and how the resulting ~22.64-cent comma reproduces Pythagorean intervals to within a fraction of a cent — is covered in full in this site's article on Holdrian commas. Attested For makam theory specifically, AEU does not treat every comma as an independent scale step. In practice, the system names roughly two dozen unequal intervals within a single octave — conventionally described as a 24-tone, 25-perde gamut — built from named comma-groupings like bakiye and küçük mücenneb rather than from equal quarter-tones. This gamut, together with a matching set of ten accidentals (five sharps, five flats), is what appears in printed Turkish notation under the AEU name today.

A contested standard

Attested AEU was disputed from within the same generation that produced it. Mahmut Ekrem Karadeniz, a theorist who corresponded directly with Ezgi and Arel around 1950, ultimately rejected their comma grid in his own treatise — completed in 1965 and published as Türk Mûsikîsinin Nazariye ve Esasları — building an alternative 41-interval framework derived from Abdülkadir Töre's tuning rather than from 53 equal commas.

Attested The more sustained modern critique comes from Ozan Yarman, whose 2008 doctoral dissertation at Istanbul Technical University weighs AEU's fixed 53-comma grid against measured performance. His acoustic analysis of recordings by master musicians — among them the neyzen Niyazi Sayın and the tanburi Necdet Yaşar — documents neutral-second-sized intervals the AEU model does not predict, and proposes an alternative 79-tone tuning as a closer fit. Attested Yarman and others have separately argued that historical Ottoman practice never adhered to any single fixed temperament, AEU's or otherwise. Uncertain Exactly how closely any specific historical period's performance matched a fixed theoretical grid is not something the surviving sources settle; treatises describe theory, not necessarily universal practice, and the two do not always align. Practice The same gap shows up inside AEU's own predictions for makams like Uşşak, where the theory's stated comma values and measured performance diverge — a tension this site covers in more detail elsewhere.

Why AEU still stands

Attested Despite these standing objections, AEU has not been displaced. Its advantages were institutional as much as acoustic: Arel's own conservatory directorship helped enshrine the system in official pedagogy at the exact moment Turkish music education was being rebuilt, and a closed, notatable, citable system was simply more useful to publishers, broadcasters, and teachers than either pure oral transmission or a rival theory with no comparable institutional backing. Attested Notably, Yarman himself teaches at the same Istanbul Technical University Turkish Music State Conservatory that has taught AEU for decades — the debate continues from inside the institution AEU built, not only from outside it. Established AEU remains the framework taught in Turkish conservatories today and the basis for the accidentals used in published Turkish notation, with the standing caveat — voiced by its own critics and successors alike — that it is a model of the tradition, not a perfect transcription of it.