symphonies, in addition to fragments of six others. While he composed no concertos, he did write three concertante works for violin and orchestra. Schubert wrote a large body of music for solo piano, including eleven incontrovertibly completed sonatas and at least eleven more in varying states of completion, numerous miscellaneous works and many short dances, in addition to producing a large set of works for piano four hands. He also wrote over fifty chamber works, including some fragmentary works. Schubert's sacred output includes seven masses, one oratorio and one requiem, among other mass movements and numerous smaller compositions. He completed only eleven of his twenty stage works. Style In July 1947 the Austrian composer Ernst Krenek discussed Schubert's style, abashedly admitting that he had at first "shared the wide-spread opinion that Schubert was a lucky inventor of pleasing tunes ... lacking the dramatic power and searching intelligence which distinguished such 'real' masters as J. S. Bach or Beethoven". Krenek wrote that he reached a completely different assessment after a close study of Schubert's pieces at the urging of his friend and fellow composer Eduard Erdmann. Krenek pointed to the piano sonatas as giving "ample evidence that [Schubert] was much more than an easy-going tune-smith who did not know, and did not care, about the craft of composition." Each sonata then in print, according to Krenek, exhibited "a great wealth of technical finesse" and revealed Schubert as "far from satisfied with pouring his charming ideas into conventional moulds; on the contrary he was a thinking artist with a keen appetite for experimentation." Instrumental music, stage works and church music That "appetite for experimentation" manifests itself repeatedly in Schubert's output in a wide variety of forms and genres, including opera, liturgical music, chamber and solo piano music, and symphonic works. Perhaps most familiarly, his adventurousness is reflected in his notably original sense of modulation; for example, the second movement of the String Quintet (D. 956), which is in E major, features a central section in the distant key of F minor. It also appears in unusual choices of instrumentation, as in the Sonata in A minor for arpeggione and piano (D. 821), or the unconventional scoring of the Trout Quintet (D. 667) for piano, violin, viola, cello, and double bass, whereas conventional piano quintets are scored for piano and string quartet. Although Schubert was clearly influenced by the Classical sonata forms of