Improvisation plays an essential role in Persian Music and it is more based on interpretation of the Dastgah feeling and principles which maestros have made. A good improvisation needs good skills on instrumental techniques or singing and complete knowledge of Dastagahs and Avazes, melody and rhythm structure of their Gushe’s and their arrangement order.
There are three methods to have a masterly performance of Persian Music
1. Even though it seems that it is not necessary to improvise in order to play the Radif, the musician does it in some cases because it is not possible to separate improvisation from Persian music.
2. In playing Phantasy music, they use unusual modulations. Performance begins in an accidental point and goes throughout the Gushes very freely.
3. Morakkab-Khani is a very difficult style when the musician starts in a certain Dastgah and then goes through some other Dastgahs and at the end goes back to the first one.
With the exception of the second one it is necessary to follow the order of Gushes. Improvisation also needs to know the usage of melodies in the modes degrees and, as Persians say, should be a maestro of the rhythm. It is also important to use embellishments based on one’s personal sense and logic.
8.1 Improvisation types
There are two improvisation types: the big improvisation and small improvisation. The big improvisation includes spontaneous innovation of the Gushes and it needs a very rare skill and inspiration. The small improvisation includes some changes in the embellishments or rhythm but limited in the structure.
8.2 Rhythm changes
It is possible to change the accents without changing the rhythm structure, using a fermata on a certain note and changing the stop points. It is also possible to play a rhythmic melody rubato or play a rubato melody in tempo.
8.3 Melody or song changes
It is possible to use some certain melody or its rhythm, and improvise through to a new melody. It is also possible to use a Gushe and change its melodic structure by adding some passing notes or make passing phrases.
8.4 Embellishment changing
Adding or changing Embellishments is another aspect of improvisation and it needs the skill and the good sense of the player.
(Safvat 2009, 153)