Protopopov, Sergei , Russian choral conductor, teacher, and composer; b. Moscow, April 2, 1893; d. there, Dec. 14, 1954. He studied medicine at the Univ. of Moscow (1913–17) and composition with Yavorsky at the Kiev Cons. (1918–21). He was active as a choral conductor and later taught at the Moscow Cons. (1938–43). His piano sonatas reflect the influence of Yavrosky’s theory of model rhythms and are dissonant in the vein of the Lourié, Roslavetz, and Mossolov piano pieces of the period. His compositions included an opera, Suite of 6 Folk Pieces for Orch. (1945), Poem for Cello and Piano (1935), 3 Poems for Cello and Piano (1938), piano pieces, including 3 sonatas (1920–22; 1924; Sonata Terza, 1924–28) and 3 Preludes (1938), and and numerous songs.
—Nicolas Slonimsky/Laura Kuhn/Dennis McIntire