Piano Quintet -Die Forelle- (4th mvt.) D.667, F. Schubert

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The Trout Quintet (Forellenquintett) is the popular name for the Piano Quintet in A major, D. 667, by Franz Schubert. Rather than the usual piano quintet ensemble of piano and string quartet, the Trout Quintet is written for piano, violin, viola, cello and double bass.
The piece is known as the Trout because the fourth movement is a set of variations on Schubert's earlier Lied "Die Forelle" ("The Trout"). As typical of some other variation movements by Schubert (in contrast to Beethoven's style), the variations do not transform the original theme into new thematic material; rather, they concentrate on melodic decoration and changes of mood. In each of the first few variations, the m9ain theme is played by a different instrument or group. In the fifth variation, Schubert begins in the flat submediant (B♭ major), and creates a series of modulations eventually leading back to the movement's main key, at the beginning of the final sixth variation.
A similar process is heard in three of Schubert's later compositions: the Octet in F major, D. 803 (fourth movement); the Piano Sonata in A minor, D. 845 (second movement); and the Impromptu in B♭ major, D. 935 No. 3. The concluding variation is similar to the original Lied, sharing the same characteristic accompaniment in the piano.
Compared to other major chamber works by Schubert, the Trout Quintet is a leisurely work, characterized by lower structural coherence, especially in its outer movements and the Andante. These movements contain unusually long repetitions of previously stated material, sometimes transposed, with little or no structural reworking, aimed at generating an overall unified dramatic design. The importance of the piece stems mainly from its use of an original and innovative harmonic language, rich in mediants and chromaticism, and from its timbral characteristics. The Trout Quintet has a unique sonority among chamber works for piano and strings, due mainly to the piano part, which for substantial sections of the piece concentrates on the highest register of the instrument, with both hands playing the same melodic line an octave apart (having been freed to do so by the inclusion of both cello and bass in the ensemble). Such writing also occurs in other chamber works by Schubert, and is characteristic of Schubert's works for piano four-hands, one of his most personal musical genres.