The GrauSchumacher Piano Duo has re-recorded Stockhausen's Mantra with sound direction by Michael Acker from the SWR Experimentalstudio.

In late 1969, Heinrich Strobel, then head of the music department at Südwestfunk, commissioned Karlheinz Stockhausen to write a new piece for two pianos for the 1970 Donaueschingen Festival. Previous to that, Stockhausen had told Strobel about a vision he had during a flight to Los Angeles. The two pianists were to perform pianistic hand movements in the air when entering the stage which then, after arriving at their instruments, would become sound. Stockhausen had travelled to Osaka in March 1970 for the Expo '70 to present his music in the German Pavilion which he had helped design. During this time, the Vision for 2 pianos, as the work was originally to be called, became Mantra for 2 pianists, and the visual part was abandoned in favour of an electronic expansion. The visible non-sound of Vision thus became the by nature invisible electronic sound expansion which, however, was vaguely perceptible due to the positioning of the electronic devices next to the pianists.

Andreas Grau, Götz Schumacher and Michael Acker have enjoyed a long-standing friendship through numerous performances of the present work Mantra.