20th Century. Written in 1973 by Stjepan Sulek on a commission from the International Trombone Association and dedicated to the late William Kramer, the Sonata has gone on to become one of the most performed and recorded solos in the repertoire. A powerful, lyrical and passionate single movement work with a duration of approximately 8 minutes. Solo part is in bass clef (despite piano score image below). Range is low F (F2) to high Bb (Bb4).