The first movement of the D major Sonata shows evidence of the new possibilities available in the cello writing with a singing, dolce first subject. Despite the Adagio being the first real slow movement of these Sonatas, the main melody is a rather restrained affair, with short rests at the end of each two-bar phrase – the smoother melodic writing is reserved for the middle section of the ABA structure. The finale follows without a break, though not before tentative attempts at the main subject forestall the arrival of the movement proper – a fully-fledged fugue. In fact this is the first occasion where Beethoven uses a fugue as the basis of a movement (instead of merely incorporating fugal writing into another form), and is thus also the first example of the contrapuntal thinking that was to dominate his final years.
from notes by Matthew Rye © 1996