Krenek’s Karl V is the kind of opera that can be appreciated on several different levels. (…) Remarkably, it’s the earliest large-scale opera to use the 12-note system, though Krenek triumphantly refutes the notion that adherence to this technique inhibits creativity and emotional power. The composer’s widow has claimed that this performance, recorded in connection with the Beethoven Festival in Bonn last year, is by far the finest she has ever heard. With wonderful singing from David Pittman-Jennings as Karl and superb commitment from conductor Marc Soustrot and his fine orchestra, there is little reason to disagree with this verdict.