Sonata in G minor W65/17 (1746)

Carl Philipp Emanuel Bach’s favourite keyboard instrument was neither the harpsichord nor the fortepiano but the clavichord, which was ideally suited to producing the “lasting, caressing tone” admired by his contemporaries. It was also uniquely equipped for the vibrato (“Bebung”) effect which he advocated in his famous Essay on the True Art of Playing Keyboard Instruments and which Burney so vividly described as “a cry of sorrow and complaint.” In fact, C.P.E. so loved his Silbermann clavichord that he wrote a “Farewell” rondo for it when he sold it. When Silbermann delivered his new fortepiano to Frederick the Great in 1746, however, Bach in his capacity as court keyboard player would obviously have been required to play it and other, similar instruments that followed. It seems likely that the present Sonata in G minor was written for Frederick’s new Silbermann fortepiano – an instrument which, incidentally, won the approval of C.P.E’s distinguished father, Johan Sebastian, when he was invited to the Royal Palace at Potsdam in 1747.

Whatever the instrument C.P.E. had in mind as he wrote, his great achievement was to do for the keyboard sonata what his father had done for the fugue. Of his 300 or keyboard pieces half of them are sonatas. He didn’t invent the form but he did establish the three-movement structure (while Domenico Scarlatti was proving himself infinitely resourceful in single-movement sonatas) and he did adapt it to the emotionally demonstrative empfindsamer Stil cultivated in northern Germany round the middle of the 18th century. It was a style which – with its expressive melody broken by silences or sighs, it sudden changes of mood, its frequent recourse to recitative, its surprising modulations and adventurous harmonies – made a profound impression on Joseph Haydn.

For anyone used to the Viennee classical style, as practised by Mozart and the later Haydn, C.P.E’s sonatas can be more than a little bewildering. The first movement, for example,    not only begins and ends with a fantasia-like cadenza but is also twice interrupted by it – which is particularly disconcerting if the cadenzas are played, as the composer recommends in his Essay, with lifted dampers. The G major Adagio, which follows without a break, is a strikingly eventful example of an expressive C.P.E slow movement. The closing Allegro assai is a fascinating, almost symbolic conflict between a pressing invitation to the fugue C.P.E. studiously avoids and a more classical-style theme which he treats with characteristic brilliance.