Music often relies on the gifts of many parts to weave it's magic. Some of those parts of easily recognisable, others seem less significant. I took a tour in Montreal once to see one of the largest organs in the world. The organ consisted of many different pipes and voices. Two or three of the pipes emit notes that are beyond the realm of human hearing. Someone on the tour asked why were they there then. If the object of an instrument is to play music, why have pipes that made no recognisable sound. The tour guide explained that it had been found that without those pipes, the whole sound of the instrument was not as rich. Even though they seemed to add nothing to the output of the sound, without them, the organ did not sound as good.