But it was not only in instrumentation that Beethoven showed his creativity. He expanded the from by writing two extended introductions to the first and last movements and by substituting a scherzo for the second minuet. It was written in 1799-1800, performed in 1800 and was a great success, so much so that Beethoven wrote a version of it for clarinet (or violin), cello and piano. Over time, Beethoven came to loathe the work because of its popularity and the continuing requests from patrons to compose more of the same kind of music.
While the Septet does resemble a serenade or divertimento, it is but a superficial resemblance. The whole character of the piece is more symphonic, a little more serious in spots and daring (even quirky). Beethoven wrote it while he was still sketching out his first symphony, so perhaps the Septet was one of the pieces Beethoven stretched his 'symphonic' muscles with to get limbered up for genuine symphonic composing. The Septet is in 6 movements:
I. Adagio; Allegro con brio - The slow, tuneful introduction leads the way for the beginning of the sonata form allegro con brio. The first theme is heard in the violin, and then taken up by the clarinet. The second theme also begins in the violin and is taken up by the clarinet. After a short section containing some new material, the exposition is repeated. The short development section begins with the opening of the first theme and explores the possibilities of material already heard. The recapitulation of the themes contain subtle changes in accompaniment and shifts in key. A coda leads to the end of the movement.
II. Adagio cantabile - A gentle, singing melody mostly played by the stars of the septet, the violin and clarinet. But Beethoven doesn't stick to the conventional division of the treble instruments playing the melody and the others the accompaniment. There is a great deal of swapping of roles.
III. Tempo di minuetto - The tune of the minuet was taken from the minuet of Beethoven's Piano Sonata Opus 49, No.2, a work that was written very early in Beethoven's career but only published later on, hence the large opus number.
IV. Tema con variazioni: Andante - A set of 5 variations on a Rhenish folk tune.
V. Scherzo: Allegro molto e vivace - The horn begins the scherzo with a rasping dotted rhythm and is a main player in the movement. The scherzo hops and prances until the trio section where the cello is in the spotlight.
VI. Andante con moto alla marcia; Presto - The introduction to the finale is rather dark and brooding, but it lasts but a short while, after which the first theme is played by violin followed by the clarinet. The horn plays a descending figure after the theme is played. Other thematic material is heard and the exposition is repeated. During the development section new themes are heard along with a short solo for violin which leads to the recapitulation. The descending figure in the horn takes a dark turn as it is given in a minor key which leads to the second theme repeat. A coda develops a fragment of the first theme until the violin takes off and the movement ends.