A complex and crucial trend back in 1970s in Iran was the westernization of traditional Persian music. This occurs in two degrees : gross alterations that produce a new hybrid music; and fine modifications in which the texture and character of the Persian music are not radically changed. The drastic changes occur in compositions outside of the radif, that is, in the tasnif, pish-daramad, and reng, the subtler alterations, in the traditional art music within the radif. This is an important distinction: the most traditional music is, by and large, not being used to create new hybrid forms. Rather, the process of hybridization occurs in music that is already one step removed from traditional Persian art music, in the nonimprovised compositions that existed side by side with the music of the radif and became more extensively practiced during the first half of the twentieth century (Source: Ella Zonis).
Graeco-Persian Musical Traditions and Their Interactions in Ancient Times
