"By 1800, Ludwig van Beethoven (1770-1827) had been in Vienna for seven years and had already established a firm reputation as both composer and pianist. In April of that year he presented a concert for his own benefit in the Burgtheater, and typically for that era, he served as publicist, ticket agent, conductor, and principal soloist. The evening included a Mozart symphony — music historians would love to know which one — arias from Haydn’s “Creation,” and a set devoted to piano improvisations. Beethoven also introduced his own Symphony #1 and Piano Concerto in B-Flat, plus a Septet for winds and strings that he dedicated to the Austrian empress, Maria Theresia. The hit of this very long evening turned out to be the Septet, which was later arranged for all manner of other instrumental combinations.
The original instrumentation, for three winds and four strings, recalls the serenades and divertimenti that Haydn, Mozart, and their contemporaries had created in great profusion a generation earlier, but even though the style was a bit outmoded, Beethoven’s inventiveness served to make the piece sound new and fun. It still delights today, with its lively themes and ingenious dialogues between two different groups of instruments, with a serene set of variations serving as its midpoint.
The Adagio introduction to the first movement features the violin, which will be one of the leading instruments throughout the piece. In the main portion of the first movement, the first theme is introduced by the violin, viola, and cello and then taken up by the clarinet, another “star” player. The development starts in c minor and features all the instruments in turn; the coda, after the recapitulation, gives a solo to the horn, one of several it will have.
“Adagio Cantabile” is the label on the second movement; this was one of Beethoven’s favorite tempo indications, the word cantabile meaning lyrical, or singing. The singing here is done by the clarinet to begin. After a light-hearted Minuet, an Andante movement presents a theme based on a German folksong, followed by five variations spotlighting in turn the strings, the clarinet and bassoon, the horn, then all together. The horn introduces the energetic and jovial Scherzo movement, whose contrasting Trio section features the violin. A slow introduction in minor introduces the finale, whose main tempo marking is Presto and whose merry main theme is announced by the strings. The wind choir has its own theme before a sparkling recapitulation and coda."
From -
http://www.rushhour.org/8-30-11/