[2] Karl Ridderbusch was born in Recklinghausen, Germany, and was discovered at an amateur music competition by the tenor Rudolf Schock who helped pay for the younger singer's training.
[4] Ridderbusch's voice ranged over two octaves,[4] allowing him to sing bass-baritone roles, such as Hans Sachs and Don Pizarro, and not just bass parts.
[3] Between then and his last appearance there in 1977, Ridderbusch sang the roles of Fasolt, Hunding, and Hagen in the Ring, Pogner and Hans Sachs in the Mastersingers, Daland in The Flying Dutchman, Titurel in Parsifal and King Marke in Tristan und Isolde.
These include the Ring, Mastersingers, Tristan, "Fidelio", Lohengrin and J. S. Bach's Mass in B minor following performances at the Salzburg Easter Festival.
Other studio collaborations include the Saint Matthew Passion with Nikolaus Harnoncourt, Leonore with Herbert Blomstedt, and Bruckner's Mass in D minor with Eugen Jochum.
Among all these, his obituarists have selected Ridderbusch's portrayal of the goldsmith Veit Pogner, the wealthiest of the Mastersingers,[1] and of the impresario La Roche in Capriccio[3] as his most memorable work in the studio.
Ridderbusch's stage presence survives on two commercial videos; as Fafner in Karajan's filming of his Salzburg Rheingold and as Kecal, the marriage broker, in a German-language version of The Bartered Bride.