Hildegard Behrens never possessed a conventionally beautiful instrument, but the power of the voice and the skill with which she wielded it made for unaccountably thrilling evenings, such as her anguished performance as Fidelio's Leonore. The sound is not great but Behrens' intensity and commitment to the drama shine through the murk. Robert Ilosfalvy is a stentorian-voiced Florestan, and the under-recorded baritone Hubert Hofmann is a nasty, biting Pizarro. Best of all is Renate Lehmann's pert, sympathetic Marzelline, who launches the great act one quartet with a beautifully-spun legato.