Excavations in Chogha Mish, about 15 miles south-east of Dezful in the province of Khoozestan have provided evidence that it was a city of considerable size in the Protoliterate period (about 5,500 years ago) when writing was probably first invented.  Most significant of the items found are the cylinder seal impressions on clay.  Per Sylvia Matheson in Persia: An Archeological Guide, "one of these gives the earliest known evidence of music as an organized art-form, showing an orchestra and a vocalist."
 

*Excerpts from "Iran & America: Rekindling a Love Lost" by Badi Badiozamani