Piano & Co: The well-tempered piano...

Johann Sebastian Bach's work on the two-part Well-Tempered Clavier, the collection of 24 preludes and fugues, took drei decades. The first part was completed in 1722. Above the surviving autograph manuscript is written in clear, engraved handwriting: "Das Wohltemperirte Clavier oder Præludia, und Fugen durch alle Tone und Semitonia, so wohl wohl tertiam majorem oder Ut Re Mi anlangend, als auch tertiam minorem oder Re Mi Fa betreffend. Composed and produced for the benefit and use of the musical youth eager to learn, as well as for the special pastime of those already habil in this studio ..." The well-tempered tuning of keyboard instruments had been introduced in 1681 by the Harz music theorist Andreas Werckmeister - it was only then that playing in all keys had become possible. in 1710, Bach's Saxon compatriot Johann David Heinichen had established the circle of fifths. Bach's cycle provided a valid and imaginative compendium of the system that was to define Western music for over two centuries. However, Bach already emphasized that his teaching work could also provide a "pastime", i.e. entertainment at the highest level.