Robert Hugill went to Cardiff to catch the revival of Yannis Kokkos's Tristan und Isolde, which first saw light 20 years ago. Has it stood the test of time? How was the singing? (Heppner/Ann Petersen/Susan Bickley) Read the full review here in Opera Today. This is the one that's being heard at the Edinburgh Festival later this summer. For those who can't afford Edinburgh, it's on in Birmingham on 16/6.