Beethoven started his career as a virtuoso pianist at a time when the piano itself was undergoing various changes, evolving from the relatively light instrument known to Mozart into a much more powerful tool. His 32 numbered sonatas (all of which are available in this Naxos series) were written after he had settled in Vienna, over a period of 25 years. Best known of all is the so-called Moonlight Sonata, with its serene opening movement and stormy finale. It is closely rivalled in popularity by the dramatic Pathétique and the imposing Appassionata Sonatas.