Karl Böhm knew that the quality of his opera productions depended heavily on the choice of the right singers for each role. “When I set my mind on doing a certain opera with a certain cast, and it doesn’t work, then I become furious and throw a fit,” he once said. In this “Così” production, Böhm has gathered some of the greatest Mozart specialists of the 20th century: Gundula Janowitz, a warm, lyric soprano whose Munich “Pamina” under Knappertsbusch was one of the high points of her early career, before she went on to sing at all major opera houses as well as the Bayreuth and Salzburg Festivals; Christa Ludwig, who began singing under Karl Böhm at the Vienna State Opera in 1955, and who was later hailed as the best Mozart and Strauss mezzo-soprano of her generation; Luigi Alva, the Peruvian tenor whose light and elegant voice has made him one of the most sought-after lyrical tenors for Rossini and Mozart roles; Hermann Prey, whose rich baritone has captivated not only the opera public the world over but also lovers of the German Lied; Walter Berry, who has sung practically the entire repertoire of great Mozart bass-baritone roles at the Salzburg Festival, the Met, Covent Garden and the Vienna State Opera.