The Dastgah Concept in Persian Music - Hormoz Farhat - Google Books

https://books.google.de/books?id=NiMhWnYDuQMC

The tradition of Persian art music embodies twelve modal systems, known as dastgahs. Each dastgah represents a complex of skeletal melodic models on the basis of which a performer produces extemporised pieces. The dastgahs revolve around unspecified…