Schoenberg’s early works are mostly Late Romantic. His piece "Verklärte Nacht" (which can be played by six string instruments or by a whole orchestra) has very beautiful harmonies which go quickly from one key to another. Gradually Schoenberg’s music changed. It became so chromatic that it was no longer in any key at all. Music like this (called “atonal”) is much harder to understand. His "Five Orchestral Pieces" were played by the conductor Sir Henry Wood at a Promenade Concert in 1912. The audience did not like it at first and took some time to get used to the sound.