Born in Plovdiv in 1915 in Plovdiv. He graduated from the State Academy of Music in Sofia in 1940.
Prof. Diamandiev started working as a teacher in the newly opened School of Music in Plovdiv, as well as a conductor of the Plovdiv Song Union. He created the first BG professional Ensamle of Folklore Songs and Dances (1948).
He was among the creators of a Academy of Music and Dances in Plovdiv (1964). He was its long-term Dean, and taught until 2002. Honorary Citizen of Plovdiv.
(His portrait above is work of the eminent Plovdiv artist, Dimiter Kirov)