Eva Quartet has been played on NTS in shows including Andy Butler / Hercules & Love Affair, featured first on 6 December 2019. Songs played include Balno Li Ti E, Sino Ljo and To Thee We Sing.

Eva Quartet is a female vocal quartet from Bulgaria specialized in Bulgarian polyphony. The four singers all come from the famous Bulgarian choir 'le mystère des voix Bulgares'. Eva Quartet sings folk songs, church music and modern compositions, all from Bulgaria. Its members are Gergana Dimitrova, soprano, Sofia Kovacheva, mezzo-soprano, Evelina Christova, alto and Daniela Stoichkova, contra-alto. Their artistic director is Milen Ivanov, who sometimes joins in singing or playing bagpipes.