The vocal quartet “Ermena” combines in itself the harmony of the voices of Sorina Bogomilova, Ralitsa Atanasova, Tanya Nedeva and Milena Stavreva, soloists of the National Folklore Ensemble of Bulgaria “Philip Koutev”.

With the Choir of the Ensemble, in which they sing together for more than15 years, they spread the beauty of the Bulgarian folk songs from Japan, through Russia and Israel, all over Europe and to the United States.They participate in various radio and television broadcasts, teach in master classes for studying Bulgarian folk songs in Bulgaria and abroad, and also in various projects with symphonic orchestras, pop and jazz formations. Some of the most exciting experiences are related to the performance of the Oratorio for the rescue of the Bulgarian Jews from the Holocaust “Melancholic Beauty” by the  composer Georgi Andreev, whose premiere was on June 21,2011,at the “Kennedy Center”,Washington, USA with the National Philharmonic Orchestra of the United States.

The special reason for the creation of Ermena Quartet was the Ladino songs project of their friend from Israel Mrs. Hamutal Zimra. At the end of January 2018 She organised few concerts in Israel and workshop for Bulgarian folklore in Nazareth and invited them and the bagpipe player Kostadin Atanasov , also soloist of the Bulgarian National Folklore Ensemble “Philip Koutev”. In April 2018 Ermena Quartet and Kostadin Atanasov was invited by Bar Ilan University of Tel Aviv to perform in a very special concert with reference to celebration of 75 years from the rescue of Bulgarian Jewish people. At the beginning of December 2018, they had another workshop in Nazareth and concert trip in Israel. They also had a concert in the Bysantine Orthodox Church in Haifa at the time of the Festival for the peace between the religions.

Ermena Quartet and Kostadin Atanasov took part in numerous concerts as part of the National Folklore Ensemble “Philip Koutev” which brings the Bulgarian folklore music heritage all over the world.