The later designation of the avaz-dastgah extended in part from melodic sections of the original seven dastgah having a degree of modal independence from their source dastgah. The discrepancy in the number of avaz-dastgah extends from disagreements about whether or not four or five distinct modal frameworks can be extracted from the dastgah of Shur.
While the numbers of notes in each modality vary in During’s interpretation of Borumand, Miller and Safvat represent all dastgah and avaz as existing within a set octave framework. Additionally, these models of modality in the system disagree on how to define the tonic of Shur, Abu ‛Ata, Dashti, Homayun, and Segah. These two interpretations also represent Homayun’s relationship with Isfahan differently, with During’s analysis reflecting different modal parameters for each one, and Miller maintaining they still share the same essential modal framework.
Though there is variation in how musicians and scholars interpret modality in the radif-dastgah tradition, the growing definition and independence of the avaz-dastgah in the twentieth century did facilitate more consistency in utilizing distinct modalities in performance. Even with this adjustment, however, there were still individual gusheh that maintained strong modal independence from the seven larger dastgah in which they appear. While some dastgah contain more modally independent gusheh than others, musicians and scholars consider modulation an inherent part of each dastgah. Shur notably contains less modulation than the rest of the dastgah. This is likely because large sections of Shur were converted into avaz-dastgah, thus removing large sections of Shur that would have constituted multiple significant modulations.
Despite the modal diversity in the gusheh, teaching and understanding the dastgah and avaz-dastgah as overarching modalities that provide the dominant modal definition in the system are quite common. Conversely, a framework of performance that emphasizes the more complex procedural aspects of the original seven dastgah remains at the core of musicians’ conceptions of the fully authentic Iranian music tradition.
Thus, traditional Iranian music in its most authentic manifestations of the late twentieth century still emphasized the melodic idiosyn crasy of the individual dastgah. If a musician or a group of musicians with a singer wanted to perform traditional Iranian music in its most authentic form, it would be the radif-dastgah tradition following a detailed procedural model: they would take one particular dastgah and perform the gusheh of it in a fairly set order, with varying degrees of improvisation on the different types of gusheh. This continued emulation of the radif-dastgah tradition’s earliest manifestations has maintained an emphasis on each dastgah’s idiosyncratic use of pitch in the course of ongoing melodic development even as notions of systematic modality have become a standard part of the tradition.
Modernization of Classic Music in Iran
