Musicians often express supreme reverence toward Mozart, and with good reason. But to think of Mozart simply as the embodiment of musical perfection is not always helpful to performers of his music. There are times when we need to be flexible and creative, and maybe just a bit less reverent.
If the goal of a performer is to bring music to life in a way similar to what the composer envisioned, then playing a Mozart concerto exactly as written is not, in fact, a great way to achieve that goal. I’ll explain why.
Professional musicians of Mozart’s time all improvised. It was a given. And Mozart, not surprisingly, was brilliant at it. His solo improvisations and piano concertos were highlights of his public concerts. In a concerto, Mozart was up in front of the orchestra showing his best stuff. This included plenty of improvisation, both along with the group and alone at specified moments throughout the piece. When you picture this, it doesn’t look all that different from Duke Ellington riffing on tunes and chord changes in front of his big band.
There is a point toward the end of many concerto movements where the orchestra pauses on a certain chord and stops, then the soloist plays on their own for up to several minutes before bringing the orchestra back in. This is called a cadenza, and in the 18th century a cadenza was normally improvised.
At least one cadenza is required by the score in most of Mozart’s piano concertos, but he didn’t always write one. If Mozart himself was playing the piece, he could simply make one up on the spot.
Mozart did write out some cadenzas to be played by his students or his sister, and modern pianists almost always play these when they’re available. But when Mozart didn’t write one, we still have to play something. It’s a bit of a dilemma if you’re not used to composing or improvising. You can get around it by finding a cadenza composed by someone else, but I think the most interesting, most authentic, and all-around best solution is to compose or improvise one.
I started improvising at a young age when I got interested in jazz, but for the longest time it never occurred to me that there was a place for improvisation in classical repertoire.
Then I came across the work of Robert Levin, an American pianist and Mozart scholar famous for improvising in the Classical style. You can hear to him do it and talk about it in fascinating detail here.
I heard Levin play two Mozart concertos at a concert in Toronto, and during his improvised cadenzas the energy in the room was electric. I was literally on the edge of my seat, wondering what would happen next.
The theorists who wrote about cadenzas in the 18th century all describe them in similar terms, as spontaneous, unpredictable flights of imagination. If you compose a cadenza in advance, they say, you must still play it as if you’re improvising.
The cadenza recalls musical ideas heard in other parts of the piece, but it turns corners and surprises you. Instead of completing a phrase with a feeling of resolution, it keeps prolonging the suspense, eventually building up to the re-entrance of the orchestra.
Now think about listening to a pianist play a cadenza that you know was written 240 years ago. Is it possible for it to communicate the same feeling of spontaneity and suspense? And at any given concert, some people will already be familiar with the concerto and will have heard the cadenza before. They are obviously not having the experience a cadenza is meant to give them.
Composing a Mozartian cadenza is actually not that hard. Anyone with the training of a concert pianist can do it with a little practice. An obvious place to start is by looking at the cadenzas Mozart wrote and following the kinds of patterns he used. After composing a few, we can begin the transition toward improvising them.
When I play a Mozart concerto, I always prepare some material to use in the cadenza. I used to write out ideas on paper, but at some point it became unnecessary. Now I store them in my brain and choose what to play in the moment. Call it improvisation or composition, or something in between (many kinds of music-making fall somewhere in between), but I can guarantee that if you hear me play a concerto live, the cadenza will be new, will surprise you, and will never be played the same way again.