The violin sonata shares a common heritage with the piano trio. Both grew out of the solo keyboard sonata. More specifically, they grew out of publishers' desires to reach a wider market with keyboard sonatas. By adding violin accompaniments to the piano works, many additional copies might be sold; the same holds true for cello parts, which could be nothing more than the left hand of the basic piano score.

By the time Beethoven comes on the scene, independence of parts had already been established. Therefore, we may consider his violin sonatas as true duo-sonatas, not piano pieces with violin ad libitum. Never mind that his title pages read Sonatas for Piano with the Accompaniment of a Violin. These works cannot be played without the fiddle, the way many an 18th-century "violin sonata" could. Nomenclature is not always accurate and traditions persist. After all, how many Haydn quartets were called divertimento, even after that form had ceased to have the function associated with entertainment music? With Beethoven's last duo we find the title "Sonata for Pianoforte and Violin." That was written in 1812 and published four years later. 

Of the ten works in this form, eight belong to Beethoven's Early period and two come from his Middle epoch. They parallel his development as a composer in the more elaborate forms of string quartet, piano sonata and symphony but do not show the tremendous strides he was making in those areas. The duo-sonata was simply not the medium for his most important statements. On the other hand, some of his most felicitous and charming moments may be found here. What could be more delightful than the "Spring" Sonata, Op. 24, which smiles from beginning to end, and even laughs out loud in the Scherzo? And if you seek classic grace and Beethoven at his most serene, then the last sonata, Op. 96 is the perfect example.