What more can I say?
Beethoven’s Piano Concerto #4 was a surprise for Viennese audiences because of its unique and creative aspects.
The “usual” beginning of concerti by Mozart and Haydn featured orchestral introductions. It was only a few bars later in this music that the piano started to develop themes that were previously played by the orchestra.
But… Beethoven did something new: The very first sounds were announced by the piano, and the orchestra joined in a few bars later.
Here is Helene Grimaud to illustrate this amazing music: