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").
Piano Quartets (Beethoven)
Each quartet is in three movements. They are listed in the order of the original manuscript:In the exposition of the first movement, Beethoven wrote a piano sonata with string accompaniment, but in the development and recapitulation, they play a more individual role. The third movement is in Rondo-sonata form. The theme is introduced by the piano and then taken by the violin. The first episode is accompanied by plucked strings. A second episode is in A minor.