Esther Doornink and Peter Elbertse play two marimbas. A marimba has a warm and full sound that combines perfectly with the harp, one of the oldest and most beautiful instruments, with the veiled sound of plucked strings. The harp has a certain mystery; all those strings in a row. The player must push himself to get the most out of the harp. Former principal timpanist of the Netherlands Philharmonic Orchestra, Peter Elbertse, is always seeking challenges (mostly within his field of rhythm and percussion), fueled by his interest in new sounds and percussion instruments.