The Hum

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The Hum is persistent and invasive low-frequency humming, rumbling, or droning noise audible to many but not all people. Hums have been reported all over the world, including the United States, the United Kingdom, Australia and Canada. [1] [2] They are sometimes named according to the locality where the problem has been particularly publicized, such as the "Taos Hum" in New Mexico and the "Windsor Hum" in Ontario.

Contents

The Hum does not appear to be a single phenomenon. Different causes have been attributed, including local mechanical sources, often from industrial plants, as well as manifestations of tinnitus or other biological auditory effects.

Description

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. These noises were often confined to a 10-kilometre (6 mi) wide area. [3]

Taos Hum

A study into the Taos Hum in the early 1990s in Taos, New Mexico indicated that at least two percent could hear it, each hearer at a different frequency between 32 and 80 Hz, modulated from 0.5 to 2 Hz. [4] Similar results have been found in an earlier British study. [5] It seems possible for hearers to move away from it, with one hearer of the Taos Hum reporting its range was 30 miles (48 km). [6] There are approximately equal percentages of male and female hearers. [4] [7] Age does appear to be a factor, with middle-aged people more likely to hear it. [8]

Auckland Hum

In 2006, Tom Moir, then of Massey University in Auckland, New Zealand, made several recordings that appeared to be the Auckland Hum. [9] [10] His previous research using simulated sounds had indicated that the hum was around 56 hertz. [11]

Windsor Hum

In late 2011, residents of Windsor, Ontario, began reporting a low droning vibration, sometimes loud enough to be irritating (one evening in 2012 saw 22,000 reports to officials). It was estimated that the sound was emanating from Zug Island, a heavily industrialized section of River Rouge on the north bank of the Detroit River (which separates Windsor and Detroit). [12] Canadian officials requested US assistance in determining the source, but local authorities were stymied by official refusals to allow access to the island. [13] A steel mill operated by U.S. Steel was the possible cause, but officials stated that no new equipment had been installed or activated around the time that the noise became noticeable. When the blast furnaces were deactivated in April 2020, the noise went away as well. [13] [14]

Other

In 2021, hums were reported in Frankfurt and Darmstadt, in Germany. [15] A year later, multiple sources for the hum were identified in Darmstadt: two faulty air conditioner units, a faulty heat pump, and three structural noise protection measures on energy generation plants. [16]

In 2022, hums were reported in St. Louis County, Missouri and surrounding areas. [17]

In 2023, a hum was reported in Omagh in Northern Ireland. [18]

Possible explanations

High-pressure gas pipelines

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. [20] In all reported cases Kohlhase studied, he said that the locations were along high-pressure gas pipelines, or at least in close proximity to them. [19]

Background sounds

In 2009, the head of audiology at Addenbrooke's Hospital in Cambridge, David Baguley, said he believed people's problems with the hum were based on the physical world about one-third of the time, and stemmed from people focusing too keenly on innocuous background sounds the other two-thirds of the time. [1] Baguley said for example the noise can be attributed to environmental causes, such as industrial machinery at a nearby factory or an industrial fan. [1] [19] But he also found that the majority of cases remain unexplained. Baguley said, "I think most people view the hum as a fringe belief because it's so subjective — people say they hear something that most people can't hear. But when you look at the vast number of people who say they hear it, it's obvious that there's something going on." [19] Baguley also theorizes that peoples' hearing has become overly sensitive. [1]

Mechanical devices

Although some form of mechanical source is an obvious candidate, given the common description of the hum as sounding like a diesel engine, the majority of reported hums have not been traced to a specific mechanical source. [1]

In the case of Kokomo, Indiana, a city with heavy industry, the origin of the hum was thought to have been traced to two sources. The first was a 36 Hz tone from a cooling tower at the local DaimlerChrysler casting plant and the second was a 10 Hz tone from an air compressor intake at the Haynes International plant. [21] After those devices were corrected, however, reports of the hum persisted. [22]

Three hums have been linked to mechanical sources. The West Seattle Hum was traced to a vacuum pump used by CalPortland to offload cargo from ships. After CalPortland replaced the silencers on the machine, reports of the hum ceased. [23] Likewise, the Wellington Hum is thought to have been due to the diesel generator on a visiting ship. [24] [25] A 35 Hz hum in Windsor, Ontario, is thought to have originated from a steelworks on the industrial zone of Zug Island near Detroit, [26] with reports of the noise ceasing after the U.S. Steel plant there ceased operations in April 2020. [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. The substation is home to the state's largest transformer. One local couple sued the power company for the disruption the hum was causing them. [27] The hum was louder inside their house than out, in part, they believed, because their house vibrated in resonance to the 60 Hz hum. In the lawsuit they claimed that the volume of the hum was measured at up to 64.1 dB in the couple's home. [28]

Some researchers speculate that the very low frequency radio waves or extremely low frequency radio waves of the military TACAMO system, used by aircraft to communicate with submarines, might be the source for the hum. David Deming observes that the difficulty of locating a source of the hum could be attributed to its broadcast from moving aircraft in this fashion, although he notes that there have never been any reports of the Hum around the U.S. Navy's stationary broadcast stations at Cutler, Maine, and Jim Creek, Washington. [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. [29]

Tinnitus

A suggested diagnosis of tinnitus, a self-reported disturbance of the auditory system, is used by some physicians in response to complaints about the Hum. [30] Tinnitus is generated internally by the auditory and nervous systems, with no external stimulus. [31]

While the Hum is hypothesized by some to be a form of low frequency tinnitus [7] such as the venous hum, some report it not to be internal, being worse inside their homes than outside; however, others insist that it is equally bad indoors and outdoors. Some people notice the Hum only at home, while others hear it everywhere they go. 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. [32]

Spontaneous otoacoustic emissions

Human ears generate their own noises, called spontaneous otoacoustic emissions (SOAE). Various studies have shown that 38 to 60 percent of adults with normal hearing have them, although the majority are unaware of these sounds. [33] The people who do hear these sounds typically hear a faint hissing (cicada-like sound), buzzing or ringing, especially if they are otherwise in complete silence. [34] Hence, researchers who looked at the Taos Hum considered otoacoustic emissions as a possibility. [35]

Jet stream

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. [3] Geoff Leventhall of the Chelsea College Acoustics Group dismissed this suggestion as "absolute nonsense". [3]

Animals

The midshipman fish was considered as a possible cause of the West Seattle Hum. Plainfin Midshipman cropped.jpg
The midshipman fish was considered as a possible cause of the West Seattle Hum.

One of the many possible causes of the West Seattle Hum considered was that it was related to the midshipman fish, also known as a toadfish. [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. [37] However, in that case the hum was resonating through houseboat hulls and affecting the people living on those boats. In the West Seattle case, the University of Washington researcher determined that it would be impossible for any resonating hum, transmitted via tanker or boat hulls, to be transmitted very far inland, certainly not far enough to account for the reports. [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. [39] The council believed this to be unlikely, since such fish are not commonly found in inshore waters of the UK. [40] As of February 2014, although the source had still not been located, the Hythe hum had been recorded. [41] [ citation needed ]

Treatment

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. [1]

Geoff Leventhall, a noise and vibration expert, has suggested cognitive behavioral therapy (CBT) may be effective in helping those affected: [42] "It's a question of whether you tense up to the noise or are relaxed about it. The CBT was shown to work, by helping people to take a different attitude to it." [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. [45] BBC Radio 4 featured an investigation of the Hum phenomena in their Punt PI fact-based comedy programme. [46] [47] In October 2022, the Norwegian state broadcaster NRK covered the Hum in its Oppdatert podcast. [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. The story editors described the episode as having "an X-Files feel". [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. It was adapted into a BBC series of the same name by the BBC in 2024.

In a 2022 episode of the animated series American Dad titled “Echoes", Avery Bullock (voiced by Patrick Stewart) muses about a mysterious background hum that several characters report hearing through the episode. [52]

The Windsor Hum is the subject of the song "The Hum" by Canadian musician Dan Griffin, [53] and the short documentary film Zug Island by Nicolas Lachapelle. [54]

See also

Related Research Articles

<span class="mw-page-title-main">Acoustics</span> Branch of physics involving mechanical waves

Acoustics is a branch of physics that deals with the study of mechanical waves in gases, liquids, and solids including topics such as vibration, sound, ultrasound and infrasound. A scientist who works in the field of acoustics is an acoustician while someone working in the field of acoustics technology may be called an acoustical engineer. The application of acoustics is present in almost all aspects of modern society with the most obvious being the audio and noise control industries.

Tinnitus is a condition when a person hears a ringing sound or a different variety of sound when no corresponding external sound is present and other people cannot hear it. Nearly everyone experiences faint "normal tinnitus" in a completely quiet room; but this is of concern only if it is bothersome, interferes with normal hearing, or is associated with other problems. The word tinnitus comes from the Latin tinnire, "to ring". In some people, it interferes with concentration, and can be associated with anxiety and depression.

<span class="mw-page-title-main">Infrasound</span> Vibrations with frequencies lower than 20 hertz

Infrasound, sometimes referred to as low frequency sound or subsonic, describes sound waves with a frequency below the lower limit of human audibility. Hearing becomes gradually less sensitive as frequency decreases, so for humans to perceive infrasound, the sound pressure must be sufficiently high. Although the ear is the primary organ for sensing low sound, at higher intensities it is possible to feel infrasound vibrations in various parts of the body.

Room acoustics is a subfield of acoustics dealing with the behaviour of sound in enclosed or partially-enclosed spaces. The architectural details of a room influences the behaviour of sound waves within it, with the effects varying by frequency. Acoustic reflection, diffraction, and diffusion can combine to create audible phenomena such as room modes and standing waves at specific frequencies and locations, echos, and unique reverberation patterns.

<span class="mw-page-title-main">Missing fundamental</span> Acoustic phenomenon

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<span class="mw-page-title-main">Sonic weapon</span> Weapon that uses soundwaves against people

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<span class="mw-page-title-main">Equal-loudness contour</span> Frequency characteristics of hearing and perceived volume

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<span class="mw-page-title-main">Sensorineural hearing loss</span> Hearing loss caused by an inner ear or vestibulocochlear nerve defect

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<span class="mw-page-title-main">Otoacoustic emission</span> Sound from the inner ear

An otoacoustic emission (OAE) is a sound that is generated from within the inner ear. Having been predicted by Austrian astrophysicist Thomas Gold in 1948, its existence was first demonstrated experimentally by British physicist David Kemp in 1978, and otoacoustic emissions have since been shown to arise through a number of different cellular and mechanical causes within the inner ear. Studies have shown that OAEs disappear after the inner ear has been damaged, so OAEs are often used in the laboratory and the clinic as a measure of inner ear health.

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References

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  2. ↑ "Mystery 'hum' baffles Inner West residents". Sydney Sentinel. 15 December 2020.
  3. 1 2 3 "Can some people hear the jet stream?". New Scientist. 8 November 1973. pp. 415–416.
  4. 1 2 "The mystery of the Taos hum" (PDF). Acoustical Society of America . Autumn 1995. Archived from the original (PDF) on 16 August 2014.
  5. ↑ "Mystery of people who hear the hum". New Scientist . 13 December 1979. pp. 868–870.
  6. ↑ "Hmmmmmmmmmmmm...?". People . 21 September 1992.
  7. 1 2 "The Phenomenon of Low Frequency Hums". Norfolk Tinnitus Society. 1993.
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  12. ↑ Josh Hafner (7 March 2016). "A Strange Hum Is Haunting Residents of a Canadian City". USA Today. Retrieved 6 August 2021.
  13. 1 2 Miellyn Fitzwater Barrows; Dallas Taylor (4 August 2021). "The Windsor Hum". Twenty Thousand Hertz . Retrieved 6 August 2021.
  14. 1 2 "Infamous 'Windsor Hum' finally dies down as U.S. Steel idles". Canadian Broadcasting Corporation . 27 July 2020.
  15. ↑ "Mysterious Hum in Darmstadt (in German)". 25 April 2021. Archived from the original on 26 April 2021.
  16. ↑ Germany, hessenschau de, Frankfurt (10 August 2022). "Nach langer Suche: Darmstadt findet erste Ursachen für störendes Brummen". hessenschau.de (in German). Retrieved 14 November 2023.{{cite web}}: CS1 maint: multiple names: authors list (link)
  17. ↑ "Strange low repeating noise under investigation in north St. Louis County". 21 February 2022.
  18. ↑ Macauley, Conor (15 November 2023). "Omagh's mystery hum keeps Tyrone residents awake". RTÉ .
  19. 1 2 3 4 Buder, Emily (18 July 2019). "The Unexplained Noise 2 Percent of People Can Hear". The Atlantic . Retrieved 31 May 2024.
  20. ↑ Harkawik, Garret (2019). "Doom Vibrations" . Retrieved 31 May 2024.
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  22. ↑ "Expert says hum is not a sound". Kokomo Tribune . 3 June 2004. pp. 1, 12.
  23. ↑ "'The Hum' followup: CalPortland installs second silencer, hopes that's the fix". West Seattle Blog . 7 December 2012.
  24. ↑ "Wellington hum disappears". 3 News. 16 October 2012.
  25. ↑ "Singapore's frigate 'Stalwart' source of Wellington hum?". 3 News. 11 October 2012.
  26. ↑ "Report: Windsor Hum Likely From Zug Island "Blast Furnace Operations"". windsoriteDOTca. 23 May 2014.
  27. ↑ "Question of noise: Couple blame electrical substation for medical issues". Charleston Post & Courier. 25 May 2013.
  28. ↑ "Myrtle Beach area couple's suit says Santee Cooper substation caused medical issues". My Horry News. 15 April 2014.
  29. 1 2 Deming, David (2004). "The Hum: An Anomalous Sound Heard Around the World". Journal of Scientific Exploration. 18 (4): 571–595. CiteSeerX   10.1.1.518.9056 .
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  31. ↑ "Tinnitus". American Academy of Otolaryngology–Head and Neck Surgery.
  32. ↑ "Expert has the answer to Woodland village hums". The Advertiser Series . 23 August 2011.
  33. ↑ Baguley, David; Andersson, Gerhard; McFerran, Don; McKenna, Laurence (2013). Tinnitus: A Multidisciplinary Approach. John Wiley & Sons. p. 244. ISBN   978-1-86156-403-0.
  34. ↑ Abrams, M. (October 1995). "An Inescapable Buzz". Discover Magazine : 20.
  35. ↑ "In Taos, Researchers Can Hum It, but They Can't Name That Sound". LA Times . 1 September 1993.
  36. ↑ "Seattle 'Hum' May Be Due To Midshipman Fish That Produce Sound For Mating". The Huffington Post . 7 September 2012.
  37. ↑ "Humming Toadfish Are the Buzz of Sausalito". NBC . 16 June 1986.
  38. ↑ "West Seattle's now-famous 'Hum': Apparently NOT a fish's fault". West Seattle Blog. 11 September 2012.
  39. ↑ "Mystery hum keeping people awake may be love-making fish". The Daily Telegraph . 23 October 2013.
  40. ↑ "Southampton Water mystery droning prompts more moaning". BBC News. 24 October 2013.
  41. ↑ "Minutes of a meeting of the New Forest Environmental Protection Liaison Committee" (PDF). New Forest District Council . 7 February 2014. p. 4. Archived from the original (PDF) on 29 April 2014.
  42. ↑ Brown, Jonathan (July 2011). "In search of the thing that goes hum in the night" . The Independent . Archived from the original on 18 June 2022.
  43. ↑ BBC News (13 June 2011). "Who, What, Why: Why is 'the hum' such a mystery?". BBC News.
  44. ↑ Unsolved Mysteries: Ghosts (DVD). First Look Studios. 2005.
  45. ↑ "Spooky! The Top 10 Unexplained Phenomena". LiveScience . 10 January 2007.
  46. ↑ "There's A Kind of Hum". Punt PI . BBC Radio 4. 13 August 2016.
  47. ↑ "Episodes to download: There's a Kind of Hum". Punt PI . BBC Radio 4. 13 August 2016.
  48. ↑ "The Hum: jakten på den mystiske lyden - Oppdatert" (in Norwegian). NRK Radio. Retrieved 21 October 2022.
  49. ↑ "In a Tiny English Town, a 'Hum' Pierces Each Night". All Things Considered . NPR. 15 June 2011.
  50. ↑ "Drive". Ten Thirteen Productions . The X-Files . 15 November 1998. Event occurs at 40:00.
  51. ↑ Cohn, Paulette (18 April 2018). "Criminal Minds Boss Erica Messer Answers Burning Questions for the Season 13 Finale". Parade . Retrieved 9 August 2021.
  52. ↑ joeyblowey (13 December 2022). "American Dad! (S19 E21) "ECHOES"". The Avocado. Retrieved 6 October 2023.
  53. ↑ "New Music From Dan Griffin, "The Hum" – Indie Music Filter". indiemusicfilter.com. Retrieved 2 August 2023.
  54. ↑ Jean-Christophe Laurence, "Le malaise avec Monk…". La Presse , 17 November 2022.

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