Piano sonatas (Beethoven)
Ludwig van Beethoven wrote his 32 piano sonatas between 1795 and 1822. Although originally not intended to be a meaningful whole, as a set they compose one of the most important collections of works in the history of music. Hans von Bülow called them "The New Testament" of the piano literature (Johann Sebastian Bach's "The Well-Tempered Clavier" being "The Old Testament").
String Trios, Op. 9 (Beethoven)
The three String Trios, Op. 9 were composed by Ludwig van Beethoven in 1797–98. He published them in Vienna in 1799, with a dedication to his patron Count Johann Georg von Browne (1767–1827). They were first performed by the violinist Ignaz Schuppanzigh with two colleagues from his string quartet. According to the violinist and conductor Angus Watson, these were probably Franz Weiss on viola and either Nikolaus Kraft or his father Anton on cello. Each of the trios consists of four movements:Although this opus does not contain the most played works by Beethoven it was a significant milestone in his development as a composer. At the time of publication the 28-year-old Beethoven regarded the trios as his best compositions. The trios can be seen as a part of the preparation for the upcoming string quartets, which became the leading genre among his chamber music. The musicologist Gerald Abraham has remarked that in terms of their style and aesthetic value the string trios of Op. 9 rank with Beethoven's first string quartets which ousted the trios from the concert halls. Beethoven composed no further trios after the first quartets (Op. 18) were published in 1801. Each trio is of four movements with sonata form in the first movements, suggesting that Beethoven did not intend them to be light chamber pieces.