Daniil Sayapin, singer and researcher, was born in 1974 in the Moscow region and comes from a family of musicians. In 1988 he graduated in piano and trumpet. The interest in ancient Russian church music in the late 1980s was accompanied by his study of scholarly works of Soviet musicologists Viktor Belyayev, Maxim Bashnikov and Nikolai Uspensky. In 1994 he graduated from the Kolomna Theological Se-minarie where he studied choral art. In the seminary in 1992 he organized his first concert for choir with old Russian choral works. After completing the seminary, he founded he founded a choir at the Church of St. Simeon in Moscow that performs exclusively performed old Russian music from 15th to 18th century- performed. The lack of singing material needed for the annual cycle of the church service became a stimulus for his study of handwritten musical material. Since the mid-1990s, his research of song manuscripts in a variety of Russian archives had already taken on a sys-tematic character. During this time, Sayapin also made use a special alphabet for reading ancient manuscripts of nevma (ancient symbols) for which he created a catalog of manuscripts containing polyphonic works of the 16th and 17th centuries. In 2003 Daniel became a singer of the choir "Old Russian Chant under the direction of Anatoly Grindenko. From 2010 to the present he sings in the ensemble of ancient Russian sacred music 'Sirin' under the direction of Andrei Kotov. In addition, he has In 1994 he also founded his own ensemble of early music, "Ex Libris". Ex Libris', which is celebrating its 25th anniversary this year. Since the mid-1990s, "Ex Libris" has been performing ancient Russian chants, not only in liturgical practice but also in concert programs. concert programs, which are also highly Appreciated. Thus, the choir has performed in Russia, Western Europe, United States and Southeast Asia. The performance of ancient Russian music by 'Ex Libris' is recognized as a reference by many masters of domestic and foreign choral art. domestic and foreign choral art, as well as by tone-leading researchers of the old Russian musical heritage, such as Valery Polyansky (State Academic Symphony Chapel), Andrey Kotov (Sirin Ensemble), and Dominique Vellard (director 'Rencontres Internationales du Thronet' festival, France). As part of the program 'Masterpieces of Ancient Russian Vocal Art' initiated by 'Ex Libris', three CDs were recorded. In 2019, the ensemble released released the LP 'Russian Medieval Requiem'.