Half of German duo-pianist brothers Klavierduo Kontarsky. He and his brother Alfons popularized modern music for two pianists.
He and his brother performed their first public concert in 1949, choosing Concerto for Two Pianos by Stravinsky as their debut piece.
He performed with his brother until 1983 when he was paralyzed after suffering two strokes.
He and his brother often used Bernhard, their younger brother, to perform three-piano pieces.
He and his brother were also known for playing traditional pieces, such as Franz Schubert's "Fantasia in F minor."