The Hum (Paperback)

High Quality Content by WIKIPEDIA articles The Hum is a generic name for a series of phenomena involving a persistent and invasive low-frequency humming noise not audible to all people. Hums have been reported in various geographical locations. In some cases a source has been located. A Hum on the Big Island of Hawaii, typically related to volcanic action, is heard in locations dozens of miles apart. The Hum is most often described as sounding somewhat like a distant idling diesel engine. Typically, the Hum is difficult to detect with microphones, and its source and nature are hard to localize.