Talk:Infrasound

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[edit] Hearing Infrasound

What bugs me about articles on infrasound is that the first thing they all say is that it "cannot be heard by humans", I have discovered that I can hear infrasound originated by the build up of seismic tension before an earthquake within 500 miles radius (depending on magnitude). It's a very low frequency throbbing that is pulsed at irregular intervals and then seizes, or is drastically diminished in intensity, as soon as the earthquake has occured. The sound used to drive me bonkers until I discovered what it was. Now I am keeping a diary of the intensity of the noises and check once a month or so on the British Geological Survey website (http://www.earthquakes.bgs.ac.uk/) whether there had been any earthquakes, and sure enough there is always an earthquake that directly correlates to the peak-followed-by-trough in the noises that I have experienced. Most of these earthquakes are never reported in the media, you see, because they occur at sea or because noone is hurt and that's not of interest for the news... - Please tell me that I am not the only person who can hear the earth move!!! (152.78.18.62 16:41, 5 June 2007 (UTC)) (Sue, Southampton, UK)

[edit] References

Don't say the scientist use names and references


[edit] Rumors

what about the rumors of it causing gastrointestinal problems at high volume?

what about extremely loud bass in car stereos collapsing lungs that have been weakened by disease? (this is real. i read it in a news article.) - Omegatron 20:02, Nov 25, 2004 (UTC)

supposedly the ear acts as a filter (which makes sense) and since no filter is ideal, will still respond to infrasound if it is loud enough, meaning people can supposedly hear down to 10 Hz or so at tremendous amplitudes. Is this real? - Omegatron 02:08, Jan 8, 2005 (UTC)

Very loud infrasound may be perceived as vibrations in any part of the body (it's what earthquakes are).

I am fairly sure that common speakers are not capable of emitting infrasound frequencies... how should we then understand the claim that some movies, such as Irreversible, use infrasound on the viewers? --Tjfulopp 20:20, 30 Jan 2005 (UTC)

Why wouldn't they be able to? - Omegatron 21:38, Jan 30, 2005 (UTC)
Because most speakers would have a very poor response at such low frequencies. —The preceding unsigned comment was added by 82.70.145.118 (talk) 16:26, 11 April 2007 (UTC).
Professional/cinema audio equipment can commonly reproduce frequencies as low as 12Hz, and I believe Dolby Digital theoretically reproduces 'sound' as low as 3Hz. (I don't have access to the technical specs to cite them.) If someone can find the THX spec that will shed more light (or sound) on the topic. Suffice to say, it's possible. 81.101.132.174 20:09, 13 September 2007 (UTC)
What about headphones? Can they hear sense infrasound?

Perhaps this page should contain a small paragraph about the connection between infrasound and binaural beats

I don't know if I'm stretching it, but could animals detect disaster through infrasonic waves? Delete if irrelevant. Gotikplage 14:58, 18 December 2005 (UTC)

Elephants can communicate with 'infrasound' and detect impending storms, earthquakes etc in a similar way. See e.g. http://www.animalvoice.com/animalssixthsense.htm Meeprophone (talk) 20:53, 4 January 2008 (UTC)

[edit] Lower limit

Where did the lower limit of 0.001 Hz in our definition come from? All the references I can find (such as Oxford Reference Online and xreferplus.com) mention no such limit. --Heron 18:22, 25 October 2005 (UTC)

Someone who wrote the article probably thought that less than that is not a sound, but more like wind -Iopq 07:23, 17 May 2006 (UTC)
Nice point. But in that case perhaps even 0.5 Hz would equate to a blustery wind. Meeprophone (talk) 20:57, 4 January 2008 (UTC)

[edit] Vladimir Gavreau

I added a small paragraph about Vladimir Gavreau. He does not have a page about him in Wikipedia, but he is an important person to know about when dealing with infrasound. I'll include my book sources on the page as well. (Sorry I was not logged in when I decided to post that.) Gotikplage 14:36, 18 December 2005 (UTC)

look at this link please: [1] search for Gavreau. Redecke 18:20, 27 August 2006 (UTC)

[edit] miles

When mentioning miles, mention kms, and first.

[edit] lowest frequency

I was messing around with Audacity and the generate tone function, I can only hear sound at 50Hz and higher is that normal?

It's your speakers. -Iopq 07:23, 17 May 2006 (UTC)
Also remember that human hearing is generally 20hz to 20khz. But that is on average, and not everyone hears the same frequencies equally.
20khz? My physics techer envied us students in school for hearing such frequencies, and even most students didn't hear much anymore at that frequency range. Note that as we humans age, our hearing is getting worse, so someone in his or her fifties is likely to not hear sounds higher than 13 to 15khz.--210.225.86.130 (talk) 00:04, 4 February 2008 (UTC)

[edit] Effects on other sences

Dr. Ciaran O'Keefe has mentioned that infrasound that's on the coops of human hearing can play on our other senses such as 'corner-of-the-eye phenomena' (vision), however can it affect our sense of smell or any other senses? -- Fribins talk

[edit] Vic Tandy

I have added a section on research by the late Vic Tandy on Infrasound and ghosts. I have tried to back-up a lot of my text with references (hope I cited them ok - still quite new here). However, some of the information was from a talk he gave Coventry Magic Circle, and from the occasional conversations I had with him after I joined the magic society that he belonged to.StephenBuxton 21:02, 5 February 2007 (UTC)


Why does this section mention haunting of Edinburgh Castle with a link to an article about South Bridge (footnote 7)? They're at opposite ends of the town!

[edit] Radio

Bill Bailey presented a radio documentry on Infra-sound The Hunt for the Hum. You can listen to it (up until 9th feb 2007) here:http://www.bbc.co.uk/radio/aod/radio4_aod.shtml?radio4/huntforthehum

Thought you might be interested StephenBuxton 21:02, 5 February 2007 (UTC)

[edit] cite for "resonant frequency of the eye"?

The "18.98Hz" figure cited sounds like BS to me; "around 19Hz" might be quite reasonable, but with that level of significant figures? Doubtful. Anybody have a cite for the details/background of that? Eye doesn't have it. --moof 22:53, 24 February 2007 (UTC)

I had a look in Vic Tandy's report, and it cites a NASA technical report that states it is 18 Hz. I have modified the text accordingly.StephenBuxton 07:51, 22 March 2007 (UTC)


[edit] Broken Link - help please!

The link to the pdf document Ghost in the Machine no longer works, as it appears that the site no longer exists. I suspect that the site might have once belonged to Vic, and as he died a couple of years back, he isn't about to repair whatever the problem is with the site. Did anyone make a copy of the file while it was available? StephenBuxton 09:33, 27 April 2007 (UTC)

[edit] Infrasound audio file?

Could a link to one be included in the page? If not, could one be placed below? Thanks. —Preceding unsigned comment added by 71.220.206.203 (talk) 01:40, 26 October 2007 (UTC)

Please? One that is in a form that can be heard by headphones. Thank you! 163.41.138.2 03:04, 29 October 2007 (UTC)
Here's a zipped two-channel 'stereo' WAV file that is thirty seconds of pure 16 Hz sine tone followed by two seconds of silence, with identical information on both channels (monophonic). Your headphones and whatever headphone amp you have aren't likely going to be able to reproduce this very strongly; I'm going to go out on a limb and suggest that you'll be hearing more 48 Hz (3rd harmonic) than 16 Hz true sine. Or not... maybe you're one of the few who have extremely fine low frequency-capable equipment. Binksternet 06:15, 29 October 2007 (UTC)


[edit] Church organs

Somewhere, too long ago to be able to cite source, I read that the large organs of large churches and cathedrals were deliberately designed to produce very low bass notes (incorrectly called subsonics); the reason given was that this was intended to induced a sense of awe (or religious feeling). The rationale was that the vibration was picked up by the gut and was mistakenly attributed to emotion. I thought this was widely-known and commonly-accepted.
Many websites report "Longer pipes in church organs also create infrasound, which many believe gives the music a particular atmospheric power." Christianity Today reported in 2003 that two British scientists say infrasound explains why large church organs increase spiritual sentiment, --The Lesser Merlin (talk) 13:22, 7 February 2008 (UTC)

Organ pipes put out quite a lot of energy at one octave above their fundamental. The way I understand it, most of the sound one hears is this harmonic. Many of the lowest organ pipes are tuned to 16 Hz--what you hear from them is a strong 32 Hz output. Certainly, awe is a part of the resulting sound, but I would downplay the infrasound element. There is one 8 Hz organ pipe in Atlantic City; that monster is certainly an infrasound producer. Boardwalk Hall Auditorium Organ Binksternet (talk) 14:46, 7 February 2008 (UTC)
Further... Several pipes sounded together have been used to produce infrasonic beat frequencies. Binksternet (talk) 18:23, 25 May 2008 (UTC)

[edit] List of freqs

I've twice deleted the list of infrasound frequencies added by User:72.153.92.44. The deleted list makes the mistake that single frequency values are called "chords" (they are called "notes") and assumes that musical notes are what people are interested in within the subject of infrasound; most readers would be interested in physical, physiological and psychological effects. Such effects do not fall under regularly-spaced musical frequencies--they happen at all infrasound frequencies. It's debatable whether any musicality exists below 16 Hz, let alone equal-tempered note values. I see no need why this listcruft should be allowed in the article. Binksternet (talk) 15:50, 14 March 2008 (UTC)

Deleted list once again. Please discuss your intention before adding it again. Binksternet (talk) 00:10, 18 March 2008 (UTC)

[edit] Noise studies

List of noise studies that I wanted to place here as possible references:

  • Belojević G, Öhrström E, Rylander R. Effects of noise on mental performance with regard to subjective noise sensitivity. Int Arch Occup Environ Health 1992;64:293-301.
  • Benton S, Leventhall HG. Experiments into the impact of low level, low frequency noise upon human behaviour. J Low Freq Noise Vibr 1986;5:143-162.
  • Berglund B, Hassmén P, Soames Job RF. Health effects induced by low-frequency noise: A critical review. Arch Center Sensory Res 1994;1:1-28.
  • Cohen S. After effects of stress on human performance and social behaviour: A review of research and theory. Psychol Bullentin 1980; 88:1:82-108.
  • Glass DC, Singer JE. Urban stress: Experiments on noise and social stressors. Academic Press, Inc, 111 Fifth Avenue, New York, USA, 1972, pp 3-182.
  • Ising H, Braun C. Acute and chronic endocrine effects of noise: Review of the research conducted at the Institute of water, soil and air hygiene. Noise & Health 2000;7:7-24.
  • Ising H, Ising M. Chronic cortisol increases in the first half of the night caused by road traffic noise. Noise & Health 2002;7:13-21
  • Kjellberg A, Muhr P, Sköldström B. Fatigue after work in noise – an epidemiological survey study and three quasi-experimental field studies. Noise & Health 1998;1:47-55.
  • Landström U, Liszka L, Danielsson Å, Linsmark A, Lindqwist M, Söderberg L. Changes of wakefulness during exposure to infrasound. J Low Freq Noise Vibr, 1982;1:2:79-87.
  • Mirowska M. An investigation and assessment of annoyance of low frequency noise in dwellings. J Low Freq Noise Vibr 1998;17:119-126.
  • Osguthorpe DJ, Mills JH. Nonauditory effects of low-frequency noise exposure in humans. Otolaryngology – Head and Neck Surgery 1982;90:367-370.
  • Persson Waye K, Rylander R, Benton S, Leventhall HG. Effects on performance and work quality due to low frequency ventilation noise. J Sound Vib 1997;205:467-474.
  • Persson Waye K, Rylander R. The prevalence of annoyance and effects after long-term exposure to low frequency noise. J Sound Vib 2001;240:483-497.
  • Persson Waye K. Effects of low frequency noise in the occupational envirornment – present knowledge base. Proceedings of the International Congress and Exposition on Noise Control and Engineering, August, Dearborn, Mi, USA, 2002, N273.

Binksternet (talk) 18:23, 25 May 2008 (UTC)