Folk music is by far the most extensive traditional art and has slowly developed throughout the ages as a fusion of Far Eastern, Oriental, medieval Eastern Orthodox and standard Western European tonalities and modes. Bulgarian folk music has a distinctive sound and uses a wide range of traditional instruments, such as gadulka, gaida, kaval and tupan. A distinguishing feature is "extended rhythmical time", which has no equivalent in the rest of European music. The State Television Female Vocal Choir won a Grammy Award in 1990 for its performances of Bulgarian folk music. Written musical composition can be traced back to the works of Yoan Kukuzel (c. 1280–1360), but modern classical music began with Emanuil Manolov, who composed the first Bulgarian opera in 1890. Pancho Vladigerov and Petko Staynov further enriched symphony, ballet and opera, which singers Ghena Dimitrova, Boris Christoff, Ljuba Welitsch and Nicolai Ghiaurov elevated to a world-class level. Bulgarian performers have gained acclaim in other genres like electropop (Mira Aroyo), jazz (Milcho Leviev) and blends of jazz and folk (Ivo Papazov).