A lot of Frau aficionados may pass this performance by because the leading singers may not be familiar. Big mistake. They are excellent and easily match some of their better known colleagues. Winfried Zillig conducts a note complete performance for the Hessian Radio years before Sawallisch's complete studio set was made decades later.Kupper easily soars through the Empress' tessitura (including a spot on top D in her opening aria). If she isn't as intense as Rysanek dramatically, she sings the coloratura passages with greater ease. Diana Eustrati, a Greek mezzo who sang with several German houses for years, is a superb Nurse. Her voice easily encompasses the wide range of the role. Bensing's career was tragically cut short by an early death at 44. He sings the Emperor with security and imagination and is one of the few tenors who can clearly be heard on the role's final top C. Kronenberg is a strong Barak and Schluter a Dyer's Wife who doesn't wobble. It has to be admitted that by this time in her career she didn't have anything above a B-flat so she rewrites the vocal line quite a bit to accommodate that; Strauss would not have minded. A young mezzo named Christa Ludwig sings the voice of the Falcon. The sound is excellent with little or no distortion. A few brief passages (including the beginning of the final quartet) were patched in from another performance with other singers, but it's edited so skillfully you really have to be paying attention to detect them.