Those well acquainted with the life and works of Wolfgang Amadeus Mozart know that his first three concertos, the three K. 107 keyboard concertos in the keys of D major, G major, and E-flat major, are actually arrangements. His source was Johann Christian Bach, the eleventh surviving child and youngest son of Johann Sebastian, born on September 5, 1735 when Sebastian was 50. Sebastian lived for only the first fifteen years of Christian’s life, but that was more than enough time to get his son started on the pedagogical foundations of making music. After Sebastian died, Christian’s education was taken over by Carl Philipp Emanuel, Sebastian’s second surviving son.
One of the more fascinating statistics of geography is that Sebastian supposedly never went more than a distance of 30 miles from the town where he was born (Eisenach). Emanuel was a bit more travelled but never ventured beyond the borders of what is now modern Germany. Thirty years of his “professional” life were spent in the service of Crown Prince Frederick of Prussia (who would become Frederick the Great) in Berlin; and these were followed by twenty years as a “free agent” in Hamburg.
By comparison Christian was a world traveler. He spent many years in Italy starting in 1756. This period began when he took up studies with Giovanni Battista Martini (whom Leopold Mozart consulted for advice about his son’s talents) in Bologna. In 1760 he became organist at the cathedral in Milan and during that period converted from Lutheranism to Catholicism. He then travelled to London in 1762, where he remained for the rest of his life, thus leading to his being known as “the London Bach.” (The British knew him as “John Bach.”)
1762 was also the year in which Leopold took his son and daughter, Maria Anna (“Nannerl”), on a concert tour during which they performed as child prodigies. The tour took them to London in 1764 and 1765, which is where Wolfgang met Christian. During this period he composed his first two symphonies (K. 16 in E-flat major and K. 19 in D major). Most likely he composed these at the keyboard, and Leopold transcribed them as full scores. Thus the K. 107 concertos amount to a similar step of proceeding from music made at the keyboard to ensemble music; and, in at least the first of those concertos, Mozart inserted his own cadenza.
The sources for those concertos came from the second, third, and fourth keyboard sonatas in a collection of six that Christian had published as his Opus 5. (Wolfgang did not even change the keys.) At the beginning of this month Naxos released a recording of Opus 5 in its entirety performed by Rachel Heard at the fortepiano. Curiously, this recording is not yet listed on Amazon.com; but it is available for download from ClassicsOnline.
While these sonatas are sometimes performed on the harpsichord, the first edition of the score distinctly shows indications of piano and forte dynamic levels for contrast. These dynamic shifts could probably be played by a harpsichord with two keyboards, but the fact that there are times when Christian alternates the dynamic level on a measure-by-measure basis suggests that he had the fortepiano in mind. (This did not stop publisher Peter Welcker from calling these pieces harpsichord sonatas, as can be seen in the original title page shown above.) Heard is clearly sensitive to these specific requirements for dynamic level, and they definitely contribute to the music’s expressive capacity. She makes a solid case that this is music that deserves to be remembered on its own terms, rather than as a source that inspired nine-year-old Wolfgang!