Dastgāh

[1][2][3] The system of twelve dastgāhs and gushehs has remained nearly the same as it was codified by the music masters of the nineteenth century, in particular Mîrzā Abdollāh Farāhāni (1843–1918).

The Persian term dastgah can be translated as "system", and dastgāh is then "first and foremost a collection of discrete and heterogeneous elements organized into a hierarchy that is entirely coherent though nevertheless flexible.

"[5] In conventional classifications of Persian music, Abū ʿAṭā, Dashti, Afshāri, and Bayāt-e Tork are considered sub-classes of Šur dastgāh.

Likewise, Bayāt-e Esfahān is a sub-class of Homāyun, reducing the number of principal dastgāhs to a total of seven.

Less common: Note that in some cases the sub-classes (āvāzs) are counted as individual dastgāhs, yet this contradicts technicalities in Iranian music.