By the time Eduard Erdmann (1896–1958) asked Krenek for a tonal piano concerto, the young composer had already embraced atonal music. But he took on the commission, seeing it as a welcome challenge, and composed the piece in F# major. The concerto begins and ends with solos for the piano – a formal device he returned to in the two subsequent piano concertos. In the general view, Schubert’s influence on Krenek did not emerge until about 1929; but Krenek acknowledged that he was already using the “tonal artifices” he had learned from Schubert when he wrote his Op. 18 concerto in 1923.
Source : Universal Edition.