‘I was really, really scared’

‘Hi, it’s Jonas.’ When the great tenor rings from Vienna, I ask if there are any topics he wants me to avoid, such are his minders’ anxieties. ‘Ask anything,’ laughs Jonas. ‘I’m not shy.’

He is heading in from the airport to see a physio — ‘these concerts, you have to stand there all the time’ — before taking Hugo Wolf’s Italian Songbook on a seven-city Baedeker tour: Vienna, Paris, London, Essen, Luxemburg, Budapest, Barcelona. I wonder if he is aware that Wolf is a hard sell to English audiences. ‘Not just the English,’ he replies. ‘Even in Germany promoters say to me, please don’t do a Wolf-only recital, no one will buy tickets. People don’t know Wolf, so they are afraid of it.’ They shouldn’t be, he says. ‘Wolf is a fantastic composer, never too heavy, he ought to be as acceptable as Schumann or Brahms.’

The foremost German tenor since Fritz Wunderlich, Kaufmann’s presence or absence can make or break a season.