By 1753, when these pieces were composed, C.P.E. Bach had been employed for more than a decade at the court of Frederick the Great in Berlin. He had earned a reputation as an important musical personality, and was attracting a number of students. It was for the benefit of these and other keyboard students that he composed his Achtzehn Probe-Stücke in sechs Sonaten (Eighteen Sample Pieces in Six Sonatas), publishing them as a supplement to his famous ‘Essay on the True Manner of Playing Keyboard Instruments’. Each of the eighteen pieces has its own individual stamp, and might well stand alone, but with his rather ambiguous title, C.P.E. Bach also seems to have provided performers with the alternative possibility of performing them in groups of three as a set of six sonatas. Although they were composed for teaching purposes, their musical qualities are striking; in his notes included in the booklet to this disc, Miklós Spányi even offers the opinion that they are ‘among the most substantial works in the composer’s entire keyboard oeuvre. In them, Bach collected his most precious ideas, as if to demonstrate his finest skills as a composer and pedagogue as well as his ideas about the æsthetics of keyboard playing: an hour’s worth of music of pure beauty, full of the most varied and sparkling ideas.’ The performer has chosen to present these gems on the clavichord, basing his decision on Bach’s documented preference for this particular keyboard instrument, but also on the fact that the scores include occasional symbols for ‘Bebung’, or vibrato, an effect possible only on the clavichord.
