ICYMI: The Pittsburgh Symphony Orchestra is opening its Mozart Festival this weekend. I had a couple of terrific conversations with Robert Levin, the Mozart scholar and pianist, for the article. He's a treasure trove of knowledge, but alas, not all of his insights made it into the preview today. Here are a few more nuggets:
Regarding improvisation: Mozart wrote down cadenzas and embellishments for the sake of amateurs who couldn't improvise. The practice of making up music on the fly declined thanks to Beethoven, whose worsening deafness compromised his ability to play with an orchestra. The problem reached an apex in an arduous effort to perform his "Emperor" Concerto. But if Beethoven couldn't be the one improvising a cadenza, nobody would be. That opened the floodgates, and performers increasingly yielded creative control to composers, particularly in the 20th century. Now, "we train performers to be reproducers of music rather than creators," Mr. Levin said with regret.
Improvisation is one of several concert practices frequented in Mozart's time that largely have disappeared from modern practice: that his concerts were hodgepodges of movements from symphonies, concertos, arias, improvisations and so on; that those performances were typically not rehearsed; etc.
Regarding key signature: One thing to note about Mozart's Piano Concerto No. 20 is its key: D minor. The work is one of just two Mozart concertos for any scoring written in a minor key. The other is his Piano Concerto No. 24 in C minor. When music began to be used more as an "entertainment vehicle" and less connected with the church, composers skewed toward more idealistic keys, aka major keys. (Earlier music had a roughly equal distribution between major and minor keys.) Minor keys became a rare commodity; many pieces that were based in a minor key still had a triumphant quality or ended in a major key. D minor is the demonic key, according to the doctrine of the affections, a theory of musical aesthetics (which was particularly influential in the Baroque period). Mr. Levin said he often tells orchestra that "the audience should smell the sulfur" at the beginning of the third movement of the Concerto No. 20.
Regarding Horn Concerto No. 1. Mozart wrote running insults in Italian in the Concerto in D Major to Joseph Leutgeb, his friend and the musician for whom he wrote the horn concertos. Much of this commentary is not suitable for a family newspaper.
This "First" Concerto was in fact the final one Mozart wrote for horn. Forensics later proved it was written last, after a few misunderstandings had miscast it as his first. This corrected numbering makes sense, given that the second version of this concerto is also the easiest; later in his career, Leutgeb needed all the help he could get.