'I like it, carry on', said Joseph Goebbels, after listening to the trautonium, invented in Berlin. It was used first in classical music in the early 1930s. Paul Hindemith composed pieces for it. For decades it was played by one man only, Oskar Sala. Thomas Pappon spoke to him in 1997, and to Peter Pichler, who still performs on the trautonium.

Picture: Alfred Hitchcock observes Oskar Sala playing the trautonium in the latter's studio, Berlin, in 1962. Credit: Heinz Koester/ Ullstein Bild via Getty Images