Maybe the mysterious noise is from one's own living body, like what you hear when you put your fingers in your ears. In 1951, Cage visited the anechoic chamber at Harvard University... "I heard two sounds, one high and one low. When I described them to the engineer in charge, he informed me that the high one was my nervous system in operation, the low one my blood in circulation." Cage had gone to a place where he ex…
Plus, allegedly they've been able to record the Hum in some cases.