Whether as a pianist, conductor, teacher or instrument collector, Jos van Immerseel is always on the lookout for the ideal historical sound. Over the years he has managed to gather an impressive collection of historical keyboard instruments to help him investigate the connections between works, instruments, and performance techniques. In the recital he has prepared for the Ruhr Piano Festival, the Belgian musician focuses on Beethoven’s strong penchant for the keyboard instruments from the Viennese workshop of Anton Walter. Immerseel always remembers the moment when he first played Beethoven on a replica of a Walter fortepiano made by Christopher Clarke (1988): “All of a sudden, everything fell into place, and everything sounded right: from the depths of the lower range to the lofty heights of the upper notes”. Immerseel’s playing embarks us on a time machine to relive the warm, intimate sound of these historical instruments without ever losing sight of his intransigent search for the essence of timbre.