The Hum#Mechanical devices

{{Short description|Low-frequency noise not audible to all people}}

{{Other uses|Hum (disambiguation)}}

{{Use dmy dates|date=March 2024}}

The Hum is persistent and invasive low-frequency humming, rumbling, or droning noise audible to many but not all people. Hums have been reported in many countries, including the United States, the United Kingdom, Australia and Canada.{{cite web|url=https://sydneysentinel.com.au/2020/12/mystery-hum-baffles-inner-west-residents/ |title= Mystery 'hum' baffles Inner West residents|work=Sydney Sentinel|date=15 December 2020}} 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.

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 {{convert|10|km|0|adj=on}} wide area.

=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.{{cite web|url=http://acousticalsociety.org/sites/default/files/docs/echoes/v5n3.pdf|archive-url=https://web.archive.org/web/20140816151706/http://acousticalsociety.org/sites/default/files/docs/echoes/v5n3.pdf|url-status=dead|archive-date=16 August 2014|title=The mystery of the Taos hum|work=Acoustical Society of America|date=Autumn 1995}} Similar results have been found in an earlier British study.{{cite web|url=https://books.google.com/books?id=66VHTgzbIEUC&pg=PA868|title=Mystery of people who hear the hum|work=New Scientist|date=13 December 1979|pages=868–870}} It seems possible for hearers to move away from it, with one hearer of the Taos Hum reporting its range was {{convert|30|mi|km}}.{{cite web|url=http://www.people.com/people/archive/article/0,,20108651,00.html|title=Hmmmmmmmmmmmm...?|work=People|date=21 September 1992}} There are approximately equal percentages of male and female hearers.{{cite web|url=http://amasci.com/hum/tinn2.txt|title=The Phenomenon of Low Frequency Hums|work=Norfolk Tinnitus Society|year=1993}} Age does appear to be a factor, with middle-aged people more likely to hear it.{{cite web|url=http://westminsterresearch.wmin.ac.uk/4141/1/Benton_2003.pdf|title=A Review of Published Research on Low Frequency Noise and its Effects|work=Defra|page=43|date=May 2003}}

=Auckland Hum=

In 2006, Tom Moir, then of Massey University in Auckland, New Zealand, made several recordings that appeared to be the Auckland Hum.{{cite web|url=http://www.speechresearch.co.nz/hum.html|title=Auckland North Shore Hum|work=T J Moir Personal pages|date=15 November 2006|url-status=dead|archive-url=https://web.archive.org/web/20121212064745/http://www.speechresearch.co.nz/hum.html|archive-date=12 December 2012}}{{cite news|url=http://www.smh.com.au/articles/2006/11/17/1163266756133.html|title=Mystery humming sound captured|work=Sydney Morning Herald|date=17 November 2006}} His previous research using simulated sounds had indicated that the hum was around 56 hertz.{{cite news |url=http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=10407822|title=Mysterious humming driving Aucklanders 'bonkers'|work=New Zealand Herald |date=27 October 2006}}

=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).{{cite news |url=https://www.usatoday.com/story/news/nation-now/2016/03/07/strange-hum-canadian-city-windsor/81453386/|title=A Strange Hum Is Haunting Residents of a Canadian City|author=Josh Hafner|date=7 March 2016|access-date=6 August 2021|work=USA Today}} Canadian officials requested US assistance in determining the source, but local authorities were stymied by official refusals to allow access to the island.{{cite web|url=https://www.20k.org/episodes/thewindsorhum|title=The Windsor Hum|author1=Miellyn Fitzwater Barrows|author2=Dallas Taylor|date=4 August 2021|access-date=6 August 2021|work=Twenty Thousand Hertz}} 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.

=Other=

In 2021, hums were reported in Frankfurt and Darmstadt, in Germany.{{cite web |date=25 April 2021 |title=Mysterious Hum in Darmstadt (in German) |url=https://www.hessenschau.de/gesellschaft/mysterioeses-brummen-in-darmstadt-diese-dauerbeschallung-ist-psychoterror,brummton-darmstadt-100.html |url-status=deviated |archive-url=https://web.archive.org/web/20210426174856/https://www.hessenschau.de/gesellschaft/mysterioeses-brummen-in-darmstadt-diese-dauerbeschallung-ist-psychoterror,brummton-darmstadt-100.html |archive-date=26 April 2021}} 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.{{Cite web |last=Germany |first=hessenschau de, Frankfurt |date=2022-08-10 |title=Nach langer Suche: Darmstadt findet erste Ursachen für störendes Brummen |url=https://www.hessenschau.de/panorama/nach-langer-suche-darmstadt-findet-erste-ursachen-fuer-stoerendes-brummen,brummen-darmstadt-102.html |access-date=2023-11-14 |work=hessenschau.de |language=German}}

In 2022, hums were reported in St. Louis County, Missouri and surrounding areas.{{cite news|url=https://fox2now.com/news/contact-2/contact-2-strange-noise-reported-in-north-st-louis-county/|title=Strange low repeating noise under investigation in north St. Louis County|date=21 February 2022}}

In 2023, a hum was reported in Omagh in Northern Ireland.{{Cite web|url=https://www.rte.ie/news/ulster/2023/1115/1416590-hum-tyrone/|title=Omagh's mystery hum keeps Tyrone residents awake|first=Conor|last=Macauley|date=15 November 2023|work=RTÉ}}

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.{{cite web |url=https://www.theatlantic.com/video/index/593992/doom-vibrations/ |last=Buder |first=Emily |title=The Unexplained Noise 2 Percent of People Can Hear |work=The Atlantic |date=18 July 2019 |access-date=31 May 2024}} 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.{{cite web |url=https://www.garretharkawik.com/doom-vibrations |last=Harkawik |first=Garret |title=Doom Vibrations |year=2019 |access-date=31 May 2024}} 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.

=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.{{cite news|url=http://news.bbc.co.uk/1/hi/uk/8056284.stm|title=Have you heard 'the Hum'?|work=BBC News|date=19 May 2009}} Baguley said for example the noise can be attributed to environmental causes, such as industrial machinery at a nearby factory or an industrial fan. 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." Baguley also theorizes that peoples' hearing has become overly sensitive.

=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.

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.{{cite journal|last=Cowan|first=J. P.|title=The Kokomo Hum investigation|url=http://le-bruit.com/easy-media/kokomo_hum_report.pdf|journal=Acentech Project No. 615411|date=October 2003}} After those devices were corrected, however, reports of the hum persisted.{{cite web|url=https://newspaperarchive.com/us/indiana/kokomo/kokomo-tribune/2004/06-03/|title=Expert says hum is not a sound|work=Kokomo Tribune|date=3 June 2004|pages=1, 12}}

Three hums have been linked to mechanical sources. {{Anchor|West Seattle Hum }}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.{{cite news |url=http://westseattleblog.com/2012/12/the-hum-followup-calportland-installs-second-silencer-hopes-thats-the-fix/|title='The Hum' followup: CalPortland installs second silencer, hopes that's the fix|work=West Seattle Blog|date=7 December 2012}} Likewise, the Wellington Hum is thought to have been due to the diesel generator on a visiting ship.{{cite news |url=http://www.3news.co.nz/Wellington-hum-disappears/tabid/423/articleID/272915/Default.aspx|title=Wellington hum disappears|work=3 News|date=16 October 2012}}{{cite web|url=http://www.3news.co.nz/Singapores-frigate-Stalwart-source-of-Wellington-hum/tabid/423/articleID/272401/Default.aspx|title=Singapore's frigate 'Stalwart' source of Wellington hum?|work=3 News|date=11 October 2012}} A 35 Hz hum in Windsor, Ontario, is thought to have originated from a steelworks on the industrial zone of Zug Island near Detroit,{{cite web|url=http://windsorite.ca/2014/05/breaking-news-the-windsor-hum-is-real/|title=Report: Windsor Hum Likely From Zug Island "Blast Furnace Operations"|work=windsoriteDOTca|date=23 May 2014}} with reports of the noise ceasing after the U.S. Steel plant there ceased operations in April 2020.{{cite news|url=https://www.cbc.ca/news/canada/windsor/windsor-hum-zug-island-us-steel-1.5665100|title=Infamous 'Windsor Hum' finally dies down as U.S. Steel idles|work=Canadian Broadcasting Corporation|date=27 July 2020}}

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.{{cite news |url=https://www.postandcourier.com/archives/question-of-noise-couple-blame-electrical-substation-for-medical-issues/article_b5f6170c-5e9d-57e4-8d0b-dd8dcad35ca6.html|title=Question of noise: Couple blame electrical substation for medical issues|work=Charleston Post & Courier|date=25 May 2013}} 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.{{cite web|url=https://www.myhorrynews.com/news/local/carolina_forest/myrtle-beach-area-couple-s-suit-says-santee-cooper-substation/article_64dcba44-c416-11e3-9b6d-001a4bcf6878.html|title=Myrtle Beach area couple's suit says Santee Cooper substation caused medical issues|work=My Horry News|date=15 April 2014}}

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.{{cite journal |last1=Deming |first1=David |title=The Hum: An Anomalous Sound Heard Around the World |journal=Journal of Scientific Exploration |date=2004 |volume=18 |issue=4 |pages=571–595 |citeseerx=10.1.1.518.9056 }}

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.

=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.{{cite news|url=https://www.independent.co.uk/life-style/whats-that-terrible-noise-all-over-the-country-people-are-plagued-by-a-strange-hum-are-their-ears-playing-up-or-is-it-something-sinister-emma-brooker-investigates-1424317.html |archive-url=https://ghostarchive.org/archive/20220618/https://www.independent.co.uk/life-style/whats-that-terrible-noise-all-over-the-country-people-are-plagued-by-a-strange-hum-are-their-ears-playing-up-or-is-it-something-sinister-emma-brooker-investigates-1424317.html |archive-date=2022-06-18 |url-access=subscription |url-status=live|title=What's that terrible noise?|work=The Independent|date=22 June 1994}} Tinnitus is generated internally by the auditory and nervous systems, with no external stimulus.{{cite web|url=http://www.entnet.org/content/tinnitus|title=Tinnitus|website=American Academy of Otolaryngology–Head and Neck Surgery}}

While the Hum is hypothesized by some to be a form of low frequency tinnitus 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.{{cite web|url=http://www.theadvertiserseries.co.uk/news/9210463.Expert_has_the_answer_to_village_hums/|title=Expert has the answer to Woodland village hums|work=The Advertiser Series|date=23 August 2011}}

=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.{{cite book |url=https://books.google.com/books?id=h83A-Qkxk-8C&pg=PT50 |title=Tinnitus: A Multidisciplinary Approach |year=2013 |isbn=978-1-86156-403-0 |page=244 |last1=Baguley |first1=David|last2=Andersson |first2=Gerhard |last3=McFerran |first3=Don |last4=McKenna |first4=Laurence|publisher=John Wiley & Sons }} 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.{{cite journal |last=Abrams |first=M. |title=An Inescapable Buzz |website=Discover Magazine |date=October 1995 |page=20}} Hence, researchers who looked at the Taos Hum considered otoacoustic emissions as a possibility.{{cite web |url=https://www.latimes.com/archives/la-xpm-1993-09-01-mn-30113-story.html |title=In Taos, Researchers Can Hum It, but They Can't Name That Sound |work=LA Times |date=1 September 1993}}

=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.{{cite web|url=https://books.google.com/books?id=i145R0bZXMYC&pg=PP415|title=Can some people hear the jet stream? |work=New Scientist|date=8 November 1973|pages=415–416}} Geoff Leventhall of the Chelsea College Acoustics Group dismissed this suggestion as "absolute nonsense".

=Animals=

File:Plainfin Midshipman cropped.jpg 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.{{cite web|url=http://www.huffingtonpost.com/2012/09/07/seattle-hum-fish-midshipman_n_1865742.html|title=Seattle 'Hum' May Be Due To Midshipman Fish That Produce Sound For Mating|work=The Huffington Post|date=7 September 2012}} 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.{{cite web|url=http://archives.nbclearn.com/portal/site/k-12/flatview?cuecard=40085|title=Humming Toadfish Are the Buzz of Sausalito|work=NBC|date=16 June 1986}} 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.{{cite web|url=http://westseattleblog.com/2012/09/west-seattles-now-famous-hum-apparently-not-a-fishs-fault/|title=West Seattle's now-famous 'Hum': Apparently NOT a fish's fault|work=West Seattle Blog|date=11 September 2012}}

The Scottish Association for Marine Science hypothesised that the nocturnal humming sound heard in Hythe, Hampshire, could be produced by a similar "sonic" fish.{{cite news|url=https://www.telegraph.co.uk/news/newstopics/howaboutthat/10399922/Mystery-hum-keeping-people-awake-may-be-love-making-fish.html|title=Mystery hum keeping people awake may be love-making fish|work=The Daily Telegraph|date=23 October 2013}} The council believed this to be unlikely, since such fish are not commonly found in inshore waters of the UK.{{cite news|url=https://www.bbc.co.uk/news/uk-england-hampshire-24658172|title=Southampton Water mystery droning prompts more moaning|work=BBC News|date=24 October 2013}} As of February 2014, although the source had still not been located, the Hythe hum had been recorded.{{cite web |url=http://www.nfdc.gov.uk/committeedocs/nfeplc/CDM08941.pdf |title=Minutes of a meeting of the New Forest Environmental Protection Liaison Committee |work=New Forest District Council |date=7 February 2014 |page=4 |url-status=dead |archive-url=https://web.archive.org/web/20140429192150/http://www.nfdc.gov.uk/committeedocs/nfeplc/CDM08941.pdf |archive-date=2014-04-29 }}{{citation needed|reason=Minutes of committee not appearing in archived source|date=July 2023}}

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.

Geoff Leventhall, a noise and vibration expert, has suggested cognitive behavioral therapy (CBT) may be effective in helping those affected:{{cite news|title=In search of the thing that goes hum in the night|url=https://www.independent.co.uk/news/uk/this-britain/in-search-of-the-thing-that-goes-hum-in-the-night-2299300.html |archive-url=https://ghostarchive.org/archive/20220618/https://www.independent.co.uk/news/uk/this-britain/in-search-of-the-thing-that-goes-hum-in-the-night-2299300.html |archive-date=2022-06-18 |url-access=subscription |url-status=live|first=Jonathan|last=Brown|date=July 2011|newspaper=The Independent}} "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."{{cite news |title=Who, What, Why: Why is 'the hum' such a mystery? |author=BBC News |url=https://www.bbc.co.uk/news/magazine-13752688 |work=BBC News |date=2011-06-13 }}

See also

References

{{reflist|30em}}

The Listeners (TV series)

Further reading

  • Deming, D. (2004). [https://web.archive.org/web/20151212164914/https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.518.9056&rep=rep1&type=pdf The Hum: An Anomalous Sound Heard Throughout the World]
  • {{cite web |last=Fox |first=Barry |date=9 December 1989 |title=Low-frequency 'hum' may permeate the environment |url=https://books.google.com/books?id=b3Xqfc2KRo8C&pg=PA27 |work=New Scientist |page=27}}
  • {{cite journal|last=Leventhall|first=H. G.|url=http://www.noiseandhealth.org/article.asp?issn=1463-1741;year=2004;volume=6;issue=23;spage=59;epage=72;aulast=Leventhall|title=Low frequency noise and annoyance|journal=Noise & Health|year=2004|volume=6|issue=23|pages=59–72|pmid=15273024|url-status=dead|archive-url=https://web.archive.org/web/20141222092803/http://www.noiseandhealth.org/article.asp?issn=1463-1741;year=2004;volume=6;issue=23;spage=59;epage=72;aulast=Leventhall|archive-date=22 December 2014 }}
  • {{cite web|last1=Moorhouse|first1=Andy|last2=Waddington|first2=David|last3=Adams|first3=Mags|date=February 2005|url=http://archive.defra.gov.uk/environment/quality/noise/research/lowfrequency/documents/nanr45-procedure.pdf |archive-url=https://web.archive.org/web/20110704193114/http://archive.defra.gov.uk/environment/quality/noise/research/lowfrequency/documents/nanr45-procedure.pdf |archive-date=4 July 2011|title=Procedure for the assessment of low frequency noise complaints |publisher=Acoustics Research Centre, University of Salford }} [http://usir.salford.ac.uk/id/eprint/18459/ Archive 2].
  • {{cite web |last1=Mullins |first1=Joe |last2=Kelly |first2=James P. |date=Autumn 1995 |url=http://acousticalsociety.org/sites/default/files/docs/echoes/v5n3.pdf|archive-url=https://web.archive.org/web/20140816151706/http://acousticalsociety.org/sites/default/files/docs/echoes/v5n3.pdf|url-status=dead|archive-date=16 August 2014|title=The Mystery of the Taos hum|work=Echos |publisher=Acoustical Society of America}}
  • {{cite journal |last1=Vasudevan |first1=R. N. |last2=Gordon |first2=C. G.| title=Experimental study of annoyance due to low frequency environmental noise|journal=Applied Acoustics|year=1997|volume=10|issue=1|pages=57–69|doi=10.1016/0003-682X(77)90007-X }}