The first time I heard Metamorphosen I was twelve. I was in the audience listening to my father who was playing it under the baton of Daniele Gatti, now chief conductor of the Royal Concertgebouw Orchestra in Amsterdam.

I was completely shocked.

I could not believe such a piece could exist.

Richard Strauss, my favourite composer, began to write the full score on 13 March 1945, the day after the destruction of the Vienna Opera. Metamorphosen is a 'waltz-requiem', in memory of a lost civilization.

Here is the Norwegian Chamber Orchestra playing it live by heart.