The Hum

Different causes have been attributed, including local mechanical sources, often from industrial plants, as well as manifestations of tinnitus or other biological auditory effects.

A 1973 report cites a university study of fifty cases of people complaining about a "low throbbing background noise" that others were unable to hear.

The sound, always peaking between 30 and 40 Hz (hertz), was found to only be heard during cool weather with a light breeze, and often early in the morning.

[18] Industrial-facilities mechanical engineer Steve Kohlhase spent $30,000 on legal fees and equipment related to his independent investigation of the low-frequency hum.

[19] Garret Harkawiks' 2019 documentary film Doom Vibrations focused on Kohlhase's ten year journey to figure out what was causing the noise, and his theory behind it.

[14] One hum in Myrtle Beach, South Carolina, was suspected of originating at a Santee Cooper substation almost two miles away from the home of a couple who first reported it.

[29] Deming considers it significant that the Hum "avoids publicity", often subsiding in response to an increase in local press coverage, and speculates that this may be a sign that the source is anthropogenic in nature.

Some sufferers report that it is made worse by soundproofing (e.g., double glazing), which serves only to decrease other environmental noise, thus making the Hum more apparent.

[35] Philip Dickinson suggested at an Institute of Biology conference in 1973 that the 30- to 40-Hz hum could be a result of the jet stream shearing against slower-moving air and possibly being amplified by power line posts, some of which were shown to vibrate, or by rooms which had a corresponding resonant frequency.

[36] A previous hum in Sausalito, California, also on the West Coast of the United States, was determined to be the mating call of the male midshipman.

[38] The Scottish Association for Marine Science hypothesised that the nocturnal humming sound heard in Hythe, Hampshire, could be produced by a similar "sonic" fish.

[41][citation needed] At an acoustics laboratory at the University of Salford, David Baguley's research focused on using psychology and relaxation techniques to minimise distress due to the hum, which can lead to a quieting or even removal of the noise.

"[43] The Taos Hum has been featured on the TV show Unsolved Mysteries,[44] and in LiveScience's "Top Ten Unexplained Phenomena", where it took tenth place.

[48] In a 1998 episode of The X-Files titled "Drive", Agent Mulder speculates that extremely low frequency (ELF) radio waves "may be behind the so-called Taos Hum".

[49][50] In a 2018 episode of the police procedural series Criminal Minds, characters are made to commit violent acts as a result of mania caused by the Hum.

[51] Jordan Tannahill's 2021 novel The Listeners tells the story of a group of people tormented by a continuous humming noise that seemingly only they can hear.

The midshipman fish was considered as a possible cause of the West Seattle Hum.