Ludwig van Beethoven's Cello Sonata No. 3 in A major, Op. 69 was written in 1808. It consists of three movements:
- Allegro, ma non tanto
- Adagio cantabile – Allegro vivace
in contrast to the normal sonata form fast–slow–fast.
In the early 19th century, sonatas for piano and instrument were usually advertised as piano sonatas with instrumental accompaniment. Beethoven's first violin sonatas, for instance, were published as "sonatas for piano with accompaniment by the violin." The cello sonata was especially so plagued, as it grew out of sonatas for continuo; as late as the beginning of the 19th century it was still common for the cello in cello sonatas to double the left hand of the piano part, with the piano right hand playing obbligato figurations and melodies. Beethoven, indeed, is credited with composing the first cello sonatas with a written-out piano part.
The Sonata in A Major, Op. 69, dates from Beethoven's most productive compositional period. Composed in the same year were the Violin Concerto and the two piano trios of Op. 70; the same year also saw the completion and publication of the Fifth and Sixth Symphonies. The first movement opens with the cello alone; variations of its expansive main theme and a pair of contrasting secondary ideas give much cause to contrapuntal and melodic interplay between the two players. The scherzo which follows, in the tonic minor (i.e. A minor), prominently features off-beat accents and is interspersed with a trio in the major that is heard twice. The finale is preceded by a short slow introduction.