(Music Sales America). Since 1901, Otakar Sevcik's works have formed the basis of many schools of string playing around the world. Thousands of players continue to find Sevcik an invaluable aid to technical development. In practicing Sevcik, as in playing scales, etudes, or pieces there are always four main headings to consider: purity of intonation, evenness of tone, exactness of rhythm and physical freedom and ease. Opus 1 Part 1 focuses on exercises in the first position.