The German composer Richard Wagner wrote seven operas in his mature style. I’ve been going to see them in live performances for the last forty years or so – my very first was Die Walküre at English National Opera in 1983, I think. I knew most of them quite well before that. The BBC, rather astonishingly now, had devoted ten weeks to showing the famous 1976 Bayreuth centenary Ring on TV, act by act; the summer before I went to university in 1983, I splashed out on what I still think is the greatest of all opera recordings, Carlos Kleiber’s Tristan and played it into the ground.