“Ensemble” was a musical composition in the guise of an exhibition and was best experienced first with one’s eyes closed. This asked something rather unusual of the viewer, demanding that he or she stand in the middle of the gallery, forget about contemplating individual works, resist for a moment the urge to manipulate them, and give in to pure sound. Why? Because the twenty-seven contraptions assembled by curator Christian Marclay at the Philadelphia ICA were not mute objects but sound-making devices, either mechanically driven or manually activated.

Think of “Ensemble” as an ongoing interactive