Do you hear the mysterious "Global Hum"? Apparently, many of you | towns

Some of you have heard it for the first time in the 70s. One of you heard it on a hot summer day in Hampstead Heath, London. And one of you even wrote a poem about it.

On Wednesday, Philip Jaekl reported on a mysterious phenomenon known as Hum. It is thought that up to 4% of people in the world hear this strange and serious sound. Its actual source is unknown, although many listeners are in urban areas, suggesting that it could be a form of noise pollution.

Anecdotes followed one another as "buzzers" shared their experiences and tried to describe them. "An endless riff of heavy metal music … hard to say if felt or heard," said one. "An undeniable mechanical" buzz "," said another. The locations vary – from the Cheshire countryside in the UK to the island of Chichagof off the coast of Alaska, pbading through a high-rise apartment building in Sydney Australia. .

This is not the first time a buzz has made headlines. In 2016, the residents of Windsor, Canada, were struck by a puzzling noise. A study later confirmed that it was probably from the blast furnaces of a US Steel factory located on the nearby island of Zug.

This week, readers have come up with theories about what is the mysterious world wind and several more skeptical readers have questioned its existence. Glen MacPherson, Professor of Mathematics, Physics, Psychology and Russian Language and former lecturer in Mathematics Education at the University of British Columbia (UBC), who investigated the source of Hum As mentioned in several posters, the Clbadical tinnitus are profoundly different from the World Hum. "

He added: "Although it is necessary to constantly insist on the fact that there are many sounds created by human activity that can look like the Hum, and that it takes some effort and knowledge to locate them. They range from electrical noise to pumps, to industrial machinery, and so on. Once we have eliminated these sources, we end up with the global phenomenon that I study. "

"True" Hum listeners, or not, here's what our readers had to say on the subject:

How does it sound?

Ozonelayer I lived in the center of Liverpool and I often heard this strange buzzing in the middle of a calm night, although my partner never could have it. For me, it looked like a big diesel engine, probably a ship or a train, both close. However, after having "suffered" from this for months, I decided to do proper research on the movements of ships and trains in order to try to isolate the cause – discovering that this n & rsquo; Was neither one nor the other.

Some claimed that it was tinnitus …

KaterinaDelina I would like to know how tinnitus was excluded from the list of possible causes. Tinnitus can be a loud hum or a roar, it is not always loud or sharp. I have tinnitus and there are three different sounds: a high whistle, a lower bell and a low throat.

But others were not in agreement

Timbomachino, I do not think it's a tinnitus, it's a very high frequency sound. I think we're talking about 18Hz or less, which is around the area of ​​the biggest organ pipe cathedral. These pipes are designed to be more "felt" than those heard. However, as the frequency is at the limit of human hearing and we are all different, we can only hear it by a few. Anyway and whatever its source, it's annoying if you can hear it.

Jaybee UK I moved to Bristol six years ago and I started hearing that. We have been greedily following the subject since then and we are very familiar with Glen's research. For all those who casually point to tinnitus, or another internally produced phenomenon, still unexplained, explain this: I can completely eliminate snoring by using silicon ear plugs. The buzz that I hear is largely ubiquitous, but only in the interior. Often it starts at a certain time, usually between 10 pm and 100 am, but it can also be present throughout the day. It's around the 50-60Hz range.

Many were left mystified by it

Nancyloh So glad to know he has a name! I heard it three or four times in the 70's. Each time, it was at a different outdoor location in Singapore. It was not a tinnitus either from the inside but from the outside. It was a mechanical "buzz" quite noisy and undeniable. The person with whom I was also heard and we joked about UFOs.

CitizenGlenn Yes, I heard the "Hum" … I live in a building near Sydney's central business district and close to Southern Cross Drive, which I have long considered to be the cause. It is interesting to note that one of the badumptions mentioned in this article is the high speed traffic. The sound resembles a low-frequency buzz of a propeller plane that oscillates between a louder and weaker buzz. At first, I thought it was an old DC3 or similar, but it was not that. I do not hear it often but when I do it is quite noticeable.

BroadfordBoy C is in the early 1960s that I saw this as a nocturnal phenomenon when I lived on the outskirts of a big city. I know it because (I remember very well), I mentioned it in a poem that I wrote for the school magazine.

People say that they hear them at different times of the day

Tintenfische The only time I do not hear the buzz is very early in the morning when the world is asleep.

Readers offer their own explanations …

LZephania A "neurologically generated perception of sound internally" seems a likely explanation. There are a variety of similar phenomena known in medicine.

Sensel Does it mean updates and use of high-pressure natural gas pipelines in many cities and suburbs?

RoyfromBungay Maybe the hum could be "frequency beats". When you have two or more sounds of different frequencies, you get a "beat frequency", an additional frequency of the sound, which is the mathematical difference. With a large number of urban sound sources with many different frequencies. This could perhaps explain why many observers perceive sounds of different frequencies.

Some places have their own "hum"

Trevor Hutton My father was a child from the Suffolk Coast during the Second World War. He has often referred to "Suffolk Hum" or "Suffolk Noise", which, he says, is barely perceptible to man and later. There were rumors about it during the war, such as enemy tunnels, etc. One day, I took the dog out for a walk early around 5.30am. And all this time and sometime after, I could feel a constel sound that I could compare to an endless riff of heavy metal music. But it was constant, without direction and hard to say if felt or heard. It certainly was not music and I'm sure it was the sound of Suffolk.

Sblejo Taos, in New Mexico, is not what one would call a metropolis, is known for its "hum Taos", which I first heard about in the 1970s, I did not never made the experience.

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