There is another concerto that is apparently for two pianos and orchestra. It is every bit as whimsical and bouncy as many of his other works. The concerto starts out with a typical E-flat sonata-like movement. It is an allegro movement. I believe that Mozart was the king of allegros because he would do a ton of scale-wise passages in many of his works including this one where he does these rhythmic eighth note passages as he goes up the scale of E-flat in various parts of the work. The allegro ends with a striking E-flat chord before going to the next movement.
The next movement in B-flat starts with a brief passage for the strings and orchestral instruments and then gives way again to Mozart’s classic scale-ridden passages that are trademark in the classical period. He accentuates this by doing almost triadic material with harmonic passages while going up the scale. The B-flat section goes into a sort of development section half way through where the orchestra does the typical B-flat seventh to E-flat progression giving way to the piano doing a ton of trills and fancy runs (as is typical in Mozart). It can lose its luster after a while. The ears tend to grow accustomed to the progressions that are used and it is less exciting. In Mozart’s time, however, it was an exciting development. Audiences everywhere were excited about this because it was a further step in polyphony and tonal harmony. Tonal harmony was a fairly new invention in Mozart’s time.
One of the conventions in this movement and evident throughout all of Mozart’s work is his ability or knack for staying on the dominant of whatever key he’s in at any point in time. He really rubs it in to make sure you get what tonal center he will be in or where he’s going. He’s getting ready to launch!
The last movement of the piece sprawls back into a elaborate E-flat major exploration with scale passages in a triplet fashion. It is crazy what’s going on here. I love the ascent of the harmonies and the diminished chords going towards the dominant of B-flat. Then, it goes back to E-flat and comes to an end. Before the ending, it lands on an E-flat 7 chord which is the secondary dominant to B-flat. This means that Mozart uses the secondary dominant to swing around and go to C minor and toy around with harmonic exploration there. Both of the pianos are in marvelous form at the end. It’s like a brightly shining bell all the way until the end.
