Carl Phillip Emanuel Bach (1714-1788), the best known son of Johann Sebastian Bach, was the most original composer of the period between the Baroque era and the Classical period. He was one of the most brilliant keyboard players of his day and created the modern expressive school of piano writing which particularly influenced the two great Classical masters, Hayden and Mozart. Bach's music was widely known during his lifetime and is highly esteemed in the testimonials of Haydn, Mozart, Beethoven, and many others. In this century, the music of this unique artistic personality has received increasing attention, but of the composer's seven hundred or more vocal and instrumental works, nearly half are unavailable in modern editions and approximately one third have never been published.