Shortly before completing his wonderful 1982 recording of Tristan und Isolde, something upset the nervy Carlos Kleiber, and he stormed out, never to enter a studio again in his remaining 22 years.
But even the magic captured then can't match the febrile intensity of his 1974 live recording from Bayreuth. How did he achieve it?
Recently-uncovered film footage from the Bayreuth pit may provide a clue. Though the picture is grained to a ghost and the sound quality appalling, you can see - and hear - the music utterly transforming and transporting the maestro.
There are six clips - the most revealing is the last (Liebestod).
Act.1 - Prelude:
Act.2 - Scene 2 O sink hernieder, Nacht der Liebe:
Act.3 - Isolde's Liebestod: