In 2010 the RIAS Kammerchor performed Monteverdi's Vespro della Beata Vergine, 400 years after its premiere, at the Rheingau Musik Festival in Eberbach Abbey, with María Cristina Kiehr, Gerlinde Sämann, James Elliott, Andreas Karasiak, Harry van der Kamp, the Akademie für Alte Musik Berlin, conducted by Hans-Christoph Rademann.
Arman has conducted (among others) the radio choirs of the Norddeutscher Rundfunk, the Südwestrundfunk, the Österreichischer Rundfunk and the RIAS Kammerchor.
In 2010 he conducted the RIAS Kammerchor and the Akademie für Alte Musik Berlin in performances of Monteverdi's Vespro della Beata Vergine, 400 years after its premiere, including a concert at the Rheingau Musik Festival in Eberbach Abbey, with María Cristina Kiehr, Gerlinde Sämann, James Elliott, Andreas Karasiak and Harry van der Kamp.