Evaluation of the Makam Scale Theory of Arel for Music Information Retrieval on Traditional Turkish Art Music

Abstract

Current music information retrieval (MIR) methods are specifically tailored to the needs of western music. Therefore, it is not straightforward to apply these methods to non-western musics such as traditional Turkish art music (TTAM). Western music theory plays a crucial role in MIR studies. The divergence, however, between theory and practice in traditional Turkish art music (TTAM) results in a lack of a reliable theory of TTAM on which MIR techniques can be based. This is particularly true for theories regarding pitch scales and interval structures in TTAM. In this paper, we evaluate the most influential (yet disputable) theory of TTAM, Arel theory, by means of a makam classification task, to understand whether it can provide a basis for MIR studies on TTAM in a similar way western music theory provides a basis for MIR studies on western music. It is shown that Arel theory is overall successful when applied for modality finding in TTAM and that it can be improved if small modifications are introduced following pitch values obtained from musical practice.

Acknowledgements

We thank The Scientific and Technological Research Council of Turkey, TÜBİTAK for their financial support (project number 107E024).

Notes

¹Even as early as in the 13th century, the theory of Urmevi slightly diverged from the practice of his time (Marcus, 1993, p. 50).

²Although Arel–Ezgi–Uzdilek is conventionaly used to refer to the theory, we prefer to use the term ‘Arel theory’ since the theory is mainly represented by a book written by Arel, and there are slight differences among Arel, Ezgi and Uzdilek. Arel theory is also used here to imply a discourse which transcends beyond the mere theory itself.

³The Turkish term ‘makam’ (pl. makamlar) is used instead of ‘maqam’ (pl. maqamat).

⁴The term ‘traditional art music’ is used to refer to the relevant musics of Egypt and Turkey.

⁵All past theorists are considered as ethnic Turks, although many of them were non-Ottoman or even non-Turkish.

⁶Karl Signell and M. Kemal Karaosmanoğlu (quoted from Can Akkoç) shared their measurement experiences with foremost performers Necdet Yaşar and Niyazi Sayın, respectively (personal communication with Signell and Karaosmanoğlu, 6–8 March 2008, İstanbul).

⁷Only the makam saba among the makamlar used is defined in Arel theory as exceeding the range of an octave. Since we consider all makamlar within an octave, intervals higher than 53 Hc (for example 61 Hc) of saba scale are omitted.

⁸7th interval for hicaz, segah and saba makam scales are defined by Arel with respect to the seyir features of these makamlar. According to Arel, these makam scales either use 6th interval or 7th interval depending on the melodic direction (ascending or descending).

⁹ http://www.xs4all.nl/huygensf/scala/, Version 2.24j, Command language version 1.86i, Copyright Manuel Op de Coul, 2007.

¹⁰All codes for automatic classification are written in MatLab 6.1.

¹¹Detailed information about the recordings and relevant MATLAB codes can be found at project web page: http://likya.iyte.edu.tr/eee/labs/audio/Main.html.