Beethoven: Sonata No.14 in C-sharp minor, Op. 27, No. 2 (“Moonlight”) (October 8, 2006)Mozart: String Quintet No. 5 in D Major, K. 593 (October 15, 2006)Generations of writing teachers have passed down the familiar edict: write what you know. In this week’s episode of the concert we’ll hear two composers who heeded that advice. Beethoven made his recital debut as a pianist at just eight years old, and he studied and played the instrument all his life. Being a baroque keyboard player was a bit like being a modern jazz pianist today; you were expected to have a strong foundation in harmony, so that you could improvise variations or play in ensembles, where the keyboardist created his part from a harmonic score a lot like a jazz lead sheet, rather than having a completely notated part. And it can’t be coincidence that in this famous piece, the Moonlight Sonata, the emphasis is on harmony. It’s the beautiful, undulating harmonies underneath the melody that we remember. Mozart also played both violin and keyboard, but when playing chamber music with his friends the instrument he favored was the viola. And in the Mozart piece on this program the instrument he adds to the standard string quartet is an extra viola. This added richness in the middle range, combined with a string player’s ear for long, singing melodic lines, show Mozart’s inner violist.