← More thunderblogs

Latest Thunderblog

The Mysterious Hum

Thunderblog -- The Mysterious Hum

 The Mysterious Hum
By Jimmy Mikecz

You hear a low rumble that sounds like it is about a mile away. You go outside, but the annoying noise is actually louder in your house. The low hum is not an appliance, and there are no factories or highways nearby. You and a few other people in your community can hear it, but not everyone. Your spouse can’t even hear it. Are you crazy? What could it be? You can swear the odd sound is real, but you are afraid to say something.

You are not alone. For decades, many have heard this noise, called The Hum. It is usually described as a low rumble, like an external diesel-powered machine in the distance.  Conversely, many hear the low murmur internally. The steady drone is not just an irritant for people but affects their daily functioning. The Hum can be hazardous, often creating distress and contributing to a loss of sleep. The danger level ranges from a minor irritant all the way to suicide.

Reports of The Hum date back to about 1940. Media interest spiked in the 1970’s when people across the UK reported it to the BBC. Back then, an industrial noise was the most widely accepted explanation. Recently, interest in The Hum is re-emerging and additional theories are being developed.

Interactive map courtesy of

The Hum occurs mainly in North America and Europe with reports in South America, South Africa, Australia, and New Zealand as well. The interactive map above provides a picture as to where the strange noise is heard. Note the almost perfect political boundaries that The Hum occupies. For example, reports in Russia are very sparse, but neighboring countries in Europe have very high numbers of reports. It appears that heavily populated areas tend to hear The Hum more frequently.

The sonorous phenomenon has attracted researchers such as doctors, scientists, and acousticians alike. Even given the widespread research, no consensus has emerged about its origin though there are currently four prevailing theories.

The first explanation is that The Hum is a form of tinnitus. Tinnitus is a medical term referring to a “ringing in the ears” when there is no external noise present. The tinnitus theory would explain why some people hear it and others do not. However, The Hum is not spread equally across populations as tinnitus is and appears to be concentrated in certain areas. Even though tinnitus is probably not the cause, some audiologists and physicians treat patients who complain of the problem.

Dr David Baguley examining a patient

Dr. David Baguley (UK) examining a patient afflicted by The Hum.

The second idea is that The Hum is distant industrial noise. Proponents of this explanation state that industrial motors, machinery, or other equipment are the source. The problem? Not everyone in the area is affected. If it were machinery, the sound would be heard by all people equally more or less. People who hear The Hum also report it in non-noisy areas such as Taos, New Mexico.

In fact, acoustic researchers visited Taos, New Mexico to conduct research to see if they could find the source. According to the recent scientific publication, “The Hum: An Anomalous Sound Heard Around the World,” scientists attempted to detect low-frequency sound using specialized equipment but did not record anything that matched the reported sound.

Location of Taos, New Mexico

Map 1 — Taos, New Mexico. This location is one of many known specifically for its own form of The Hum

The fact that The Hum is geographically concentrated and yet not-audible to everyone has lead to the remaining two theories. Each makes the claim that The Hum is not a physically audible sound but rather a perceived sound from a non-auditory source.

Could it be that The Hum is a natural geologic phenomenon? That theory was put forward in a recent study published in Geologic Letters called “How Ocean Waves Rock the Earth and argues that ocean waves crashing on the ocean floor can cause rock layers in the earth to “ring like a bell.” This, in turn, may cause ultra-high frequency sound waves to emanate into human-occupied areas. The fact that The Hum is often heard near coastal areas like the UK, Southeast Australia, and New Zealand gives this idea some support. Conversely, it does not explain why it occurs in specific regions inland. It is unknown whether or not oceanic pounding could cause inland forms of the phenomenon.

The last prevailing theory is that The Hum is caused by some form of electromagnetic frequency (EMF) that is perceived as sound. EMF waves are unique from sound waves and are a form of common wave energy that propagates through space such as visible light, radio waves, and microwaves, which are used in microwave ovens and WiFi network communications.

It has been shown experimentally that certain EMFs can cause people to perceive sound. According to research conducted by Allan Frey in 1962, both deaf and non-deaf people could be induced to hear a noise produced by microwave radiation in the frequency range of 425-1310 MHz at 275 mW/cm^2. It should be noted that cell phone towers commonly communicate within this frequency band and power range.

Therefore, this mysterious rumble may be generated by microwave EMF though some areas of the world, particularly Asia, Africa, and South America, do not appear to be as affected. Even countries like Japan with relatively free internet report very few instances of The Hum. Whether or not there is a  language barrier in reporting is not known.


Dr. Glen MacPherson

The best course of action for those affected by The Hum is to report the phenomenon to This Website, run by Dr. Glen MacPherson a former lecturer at the University of British Columbia, allows users to make reports online. He started the project in 2012 when he heard the mysterious sound and found no place to report the incidents. The interactive map above is a product of his Website.

The Hum is a potentially hazardous, noise-like phenomena that affect many communities mainly across Europe, North America, Australia, and New Zealand. Currently, the best four explanations for the bothersome sound are tinnitus, industrial noise, geologic “ringing,” and EMF. Although well-documented and heavily researched, there is no consensus as to its origin and much speculation. Questions remain. Are all of The Hums from one source, or many? What exactly is the extent of the health hazard? Can this harmful noise be blocked by those affected?  If it is man-made, who is responsible? Could it be caused by more than one source? Those who hear The Hum are encouraged to contribute to the crowd-sourced research project at Further research is encouraged by visiting the links below.

Works Cited:

Scientific Articles:
The Hum: An Anomalous Sound Heard Around the World, Journal of Scientific Exploration, Vol. 18, No. 4, pp. 571–595, 2004, Web Access

The Mystery of the Taos Hum, The Newsletter of the Acoustical Society of America, Autumn, 1995, Web Access

How ocean waves rock the Earth: Two mechanisms explain microseisms with periods 3 to 300 s, Geophysical Research Letters, Volume 42, Issue 3 16 February 2015 Pages 765–772, Web Access 

News Sources:
Humdingers, The Guardian, 2004
Have you heard ‘the Hum’? BBC, 2009

Other resources:, Web Access

Thunderblog photo of Jimmy Mikecz cmokidoepiamiicd 150X175A native Wisconsinite, Jimmy Mikecz researches, blogs, and conducts independent research on a variety of topics. These include history, engineering, web development, comparative religion, psychology, agriculture, philosophy, and many other topics. He has a B.S. in Environmental Science from University of Wisconsin – Madison. Jimmy hosts his own website:

The ideas expressed in Thunderblogs do not necessarily express the views of T-Bolts Group Inc or The Thunderbolts ProjectTM. Edited by Susan Schirott. 

Print Friendly, PDF & Email

← More thunderblogs

Print Friendly, PDF & Email