A mysterious low-frequency sound known as The Hum has been reported around the world for decades, leaving researchers searching for its source.
Imagine lying in bed late at night and hearing a faint engine-like drone that seems to come from somewhere outside. You check the windows, listen for traffic, and search for a nearby machine. Nothing. Stranger still, the person next to you hears absolutely nothing.
For decades, people around the world have reported this unsettling experience. Known simply as The Hum, the phenomenon has sparked countless theories, scientific investigations, and even conspiracy claims. Now, researchers say the answer may lie not in the environment, but inside the human hearing system itself.
A Mystery That Refuses to Go Away
Reports of The Hum first gained widespread attention in Bristol, England, during the 1970s, when local newspapers were flooded with letters from residents describing a persistent low-frequency noise. Similar accounts soon appeared elsewhere in the United Kingdom and later spread to North America, Australia, New Zealand, South Africa, and parts of Europe.
One of the most famous cases emerged in Taos, New Mexico, where so many residents complained about hearing a mysterious low rumble that scientists were eventually called in to investigate.
Although reports come from around the world, The Hum remains surprisingly rare. Surveys suggest only a small percentage of people can hear it, which may explain why the phenomenon often leaves those affected feeling isolated or dismissed.
The sound is typically described as a distant diesel engine, an idling truck, industrial machinery, or a low electrical buzz. Many people report hearing it most clearly indoors and during quiet nighttime hours, when background noise levels drop and attention shifts toward subtle sounds.
Searching for an Invisible Source
Over the years, researchers have examined a long list of possible explanations.
Some suspected industrial equipment, ventilation systems, traffic, electrical infrastructure, or wind turbines. Others pointed to natural sources such as ocean waves, atmospheric conditions, or vibrations traveling through the ground.
The challenge is that low-frequency sounds behave differently from higher-pitched noises. Their long wavelengths allow them to travel great distances, bend around obstacles, and become difficult to pinpoint.
“We know that there are people who hear low-frequency sounds that can actually be measured, even if other people don’t hear them. But it’s not so easy to find the source of these sound waves, because it’s a struggle to localize low-frequency sounds,” said Markus Drexl, a professor at the Norwegian University of Science and Technology (NTNU).
This difficulty has often fueled speculation. When no obvious source can be found, theories ranging from secret government projects to extraterrestrial activity have inevitably emerged. Yet despite decades of investigation, no single external source has ever explained all reports of The Hum.
Testing the People Who Hear It
To better understand the phenomenon, Drexl and colleagues studied 28 people in Germany who regularly experienced an unexplained humming or buzzing sound.
The researchers first explored a straightforward possibility: perhaps people who hear The Hum simply possess unusually sensitive hearing at low frequencies.
The results offered only limited support for that idea. Most participants showed normal hearing abilities. Only two demonstrated better-than-average sensitivity at certain low frequencies.
“Even though the group we tested was small, it still means that the hypothesis of having especially good hearing for low-frequency sounds does not hold for most people,” Drexl said.
Still, he cautions that conventional hearing tests may miss extremely narrow ranges of heightened sensitivity. Someone could potentially detect sounds within a tiny frequency window that standard examinations fail to measure.
Could the Ear Be Creating the Sound?
The researchers then investigated a more surprising possibility.
The human ear is not completely silent. Deep within the inner ear, the cochlea can generate faint sounds known as otoacoustic emissions. These tiny sounds are a normal byproduct of how the ear amplifies incoming audio signals.
“Most of us don’t hear these sounds. However, a few people can actually hear the sounds that the ear itself produces. And these sounds can be measured objectively,” Drexl explained.
Because spontaneous otoacoustic emissions can sometimes be perceived as tinnitus, the team wondered whether they might account for reports of The Hum.
Testing found no evidence that this was the primary explanation for the participants in the study.
The Strongest Explanation May Be Tinnitus
That left another possibility.
“Then there are people who hear something that cannot be measured objectively. We believe people in this category have a form of low-frequency tinnitus,” Drexl said.
Most people associate tinnitus with a high-pitched ringing sound, but tinnitus can take many forms. Some people hear buzzing, roaring, clicking, hissing, or low-frequency humming.
Tinnitus is not a disease itself. It is a perception of sound generated somewhere within the auditory system without an external source.
This may explain one of the most puzzling aspects of The Hum. Many people initially believe the sound originates in their surroundings. Only after hearing it repeatedly in different locations do they begin to suspect the source may be internal.
Based on their findings, the researchers propose that The Hum likely does not have a single explanation.
Some cases may involve real environmental sounds that only a few people can detect. Others may result from low-frequency tinnitus that is perceived as an external noise.
“Based on our results, although we haven’t ruled out cases of physical external sound sources, we suggest that subjective tinnitus in the low-frequency range is often the cause of hearing pulsations of low-frequency sound perceptions,” Drexl said.
Why Scientists Are Still Interested
Drexl’s interest in The Hum stems from his broader research on low-frequency sound.
“What we know about the hearing system is mainly based on how we capture and process sound with higher frequencies. We know less about how the auditory system handles and processes low-frequency sound, or infrasound,” Drexl said.
According to Drexl, concern about noise from technical sources operating in the low-frequency range (between about 20 and 250 Hz) and the infrasound range (below 20 Hz) has increased over the past decade.
“If we want to conduct a thorough assessment of low-frequency sounds and infrasound, we first need a better understanding of how sensory systems process low-frequency sound and infrasound,” Drexl said.
Reference: “On the potential sources of a low-frequency sound percept that only a few can perceive” by Bonifaz Baumann, Andrej Voss, Carlos Jurado and Markus Drexl, 27 March 2026, PLOS ONE.
DOI: 10.1371/journal.pone.0326818
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15 Comments
Also, “There’s a Kind of Hush All Over the World tonight’
Interestingly, The Hum sounded frantically busy for the 24 hrs. ahead of, and utterly stopped during the 24 hours immediately after, the fateful 2001 Sept. event.
It also was very busy ahead of, then quit after the Shutdown commenced.
It is different from tinnitus.
The hush was indeed, all over the world, during those times; like being back in the 1950s.
It’s the mf powerlines!!!! Are you guys really that dense??? My god!
More than one “flavor” has been my experience…a veritable cornucopia of high, low, buzz, hiss (like a pinhole leak in a radiator hose)….sometimes it travels with me and other times it seems mysteriously “stationary”(not that i can ever quite pinpoint a source of course)…if i run a tub of water and duck my head under or jump in a pool and stay underwater, that nirmally silences it until i pop up and there we go again…most of the time it most resembles ciccadas….but supposedly those are dormant 11 or 17 years at a time or along those lines but i hear them ALL THE TIME…ALOT
The power lines are a different kind of vibration.
Any time I check, I hear something. I simply ignore it. I assume it’s something on the order of tinnitus, but if I never read about it, I’m not sure I would have any problem with it. Our brains automatically filter out a lot of garbage from all of our senses.
If it’s tinnitus, how come it’s in certain places? Bristol is known for it – Bath isn’t. It seems to be specific cities. I haven’t heard of it in London.
I’ve been hearing it for…at least since the early 1970s, in the States; numerous States. Various geological compositions in areas. Various building structures.
It is different from tinnitus (which I developed much later).
There’s far more going on, related to The Hum, than most have mentioned.
I’m a Hum sufferer since November of 2012. I also have had tinnitus my whole life. THE HUM IS NOT TINNITUS. My tinnitus is constant. The Hum is only indoors in certain locations. I don’t hear it outdoors. I don’t hear it when there is a lot of background noise. It’s louder at night and in cold weather and during the colder months. If it was tinnitus, I’d hear it constantly regardless of where I was or what background noises were there or what time it was or what season it was. This is simple logic. GOOD. GRIEF.
Every single so called “explanation” that I have come across for The Hum has been simply absurd. This makes me wonder if it is an organized/planned/intentional campaign of disinformation designed to gaslight the Hum sufferers in order to hide something that the governments are doing all over the world that they don’t want to admit they are doing, or they don’t want the public to know about something that is happening in nature to the planet. What other reason would they be lying and making up all this nonsense for?
Bingo!
Yes!
I disagree that it is a form of tinnitus, for actual Hum experiencers.
And, it existed other places besides coastal Britain.
Yes, there is tinnitus. But a person can have both complex tinnitus, AND also hear The Hum.
Here’s why I think this:
The Hum has been part of my life’s background for many decades. Never could figure it out.
Thot for some time it might be the earth’s hum—Schumann frequency.
That’s everywhere, all the time. It did not just start suddenly, & it does not vacillate.
Or maybe the HAARP array, which some military connections said was a method of sending covert messages to the long-submerged nuke subs (a one-way message system)—but that was not built til decades later.
One relative said it was probly tinnitus.
I’d never had that as a teen or young adult; it did not develop til in my late 40s or 50s. Yet, I can still hear The Hum.
Also, tinnitus sounds in my case, could change or stop if I adjusted my neck, pointing at it being related to nerve pinches involving cranial nerves.
& In my 70s, I also discovered tinnitus sounds could go away, if I consumed a healthier diet.
But bottom line, the tinnitus going away with repositioning my neck, never stopped The Hum, which happened at same time, &/or, independent of The Hum.
In 1972, I had my 1st pregnancy, & was on constant overwhelm from sound levels.
We lived in Junction City, KS then, in an old, converted carriage house on an alley. The Army base was a few miles away. A 4-lane road was out front of the 2 big houses in front of ours. The sheriff lived next door, & constantly left his big dog chained to the carport, barking outside our bedroom-livingroom window.
And, there was The Hum that never stopped, in the early 1970s, and still now.
I never heard it in the 1950s, anywhere I traveled or lived in CA, UT, AK, IL, AZ, NM; nor in the 1960s in CA or in UT.
But then something happened that seemed to confirm that it was indeed some covert government signaling.
First, I’d describe The Hum as a very huge generator motor, spinning on its axis.
Usually, it’s fairly even, all the time. Baseline RPMs.
It sounds to me, just like the huge generators we got to witness in action, in Hoover Dam, on a vacation (a road trip in the 1950s).
We stood in the generator “room”, inside the dam, as one of those generators was starting-up from a dead-stop. That is a sound & vibratory sensation one never forgets!
Picture hearing & feeling that, if made to run faster, slower, faster, etc., in some kind of pattern. The generators in Hoover Dam stayed at an even RPM; but The Hum did not.
Here’s what happened leading up to & beyond that September 2001 event, and why I think The Hum has everything to do with military and political activities:
Some months leading up to that 2001 event, The Hum changed remarkably, sounding like increasing and decreasing RPMs above and below the baseline RPMs, in patterns, kind of like a code; lots of it, but randomly; not too much.
At this time, we lived in an old wood frame house, on a concrete foundation, on a very river-rocky area—like pit-run gravel, in a very tiny, rural city surrounded by hills.
I figured, vibrations must have amplified thru that rocky ground & old structure.
It seemed loudest at night; I figured, traffic, industry, etc. during the day.
My spouse couldn’t hear it—probly because of his hearing loss, and his ability to fall asleep anywhere.
But, for some days ahead of the 2001 event, the “Code” RPMs of The Hum, drastically increased, especially during the 24 hours before; so loud, I struggled to sleep, and felt very tense from the seeming urgency of the patterned RPMs. Could even feel slight vibration in the wall at head of our bed; it seemed absolutely frantic in activity, constant increase and decrease of RPMs, tho I had no meter to check it.
But when the towers got hit, & a friend from church banged on our door to wake us, asking to see our TV, I realized, The Hum had gone silent.
A deep silence I had not heard since the 1950s.
Then, after roughly 24 hrs of that silence, The Hum restarted—& it sounded just like that giant Hoover Dam generator starting-up from a standstill.
Exactly.
The slow winding-up/ramping-up of RPMs of a very heavy piece of machinery spinning on an axis, until it reached its baseline operating RPMs.
And, no vacillations.
Just like how that generator had sounded, down in the dam.
Until any other big political event was going on, then there’d be some activity.
After the 2001 event, I was paying closer attention.
Then came the Shutdown in March, 2020.
Only now, we’d lived next to a joint base, & experienced very increased flights, range-fire practice.
When Shutdown was announced, kicked-off with the “joke” comment about there being a toilet paper shortage, and suddenly everything stopped & everyone stayed home, I knew something was wrong, and it was NOT what public was told it was.
I realized, The Hum had gone silent, too.
It stayed blessed silent for….days?…til at some point, it returned.
But it did not bode well.
All the JBLM (WA) military activity that had really been SO increased (like aircraft, & range-practice), long ahead of the Shutdown, had also stopped.
That returned, tho, not anything near what it had been, prior to the Shutdown.
Related History lesson:
Back in the 1950s, in the Altadena, CA area, were govt industries & Think Tanks.
Parents working in those, also sent their kids to the elementary school I attended.
It was about 1958.
Occasionally, there’d be a kid, about 3rd or 4th grader, doing a one-question survey of other kids same ages, on the playground.
Long later, I overheard the term: “playground surveys”, related to think tanks.
Two of those questions stuck in my head.
I closely observed both questions and paid attention to questions kids asked the survey kid—followed the survey kid around, to hear what they said, watch their reactions.
One was:
“If something happens that makes all food disappear, so the only thing left to eat was snails or earthworms, which would you choose to eat?”
The other was:
“If you could vote for a President of the country, and the choice was between a black man or a white woman, which would you vote for?”
Kids on that playground thot amazingly deeply and carefully before answering, and most gave the same answers, near unanimous:
“Probly worms, cuz those can fry on a sun-hot rock to taste kinda like French fries!”
“The black man, cuz people are only used to men being President; maybe later, a woman.”
Approx. 60 or so years after those playground surveys, one can find not only dried worms, but also some insect proteins for sale, online. And, there have been sporadic media pushes & discussions about it.
And, we’ve had a black man as president, & Almost a white woman after that—disrupted by DT taking the election (twice)—which was not planned by those doing the playground surveys. He was a surprise.
Based on various info, education, researches, overheard discussions, being in right place at right time, I think:
SOMEONE(s) been planning pretty much everything, Long ahead of specific things happening—& it’s about far more than who’s slotted-in as President, or whatever humans are being taught to accept as food.
And, planning has been going on far longer than the mere 60 yrs ahead of these things.
Maybe, The Hum is a communication tool that can also be used to influence human behaviors (based on how subsonic/infrasonic vibrations affect human biology, physiology, emotions and behaviors).
That is why I think The Hum is related to govt & political activity; it’s related to entities communicating about extreme events that have been planned & then put in motion.
Planned very long in advance, to manipulate populations & outcomes.
And yes, they seem to care not about “collateral damages”.
There’s far more between heaven & earth, than are dreamt of.
I have reasons to think, things have been being planned and done, not just several decades ahead, but centuries, even millennia ahead.
Researched by the Norwegian University of Science and Technology.
Entertaining paper however, everyone here is wiser than the experts! I’m with CaptainObvious; powerlines or transformers. In an age where at a minimum spectrum analyzers exist, technology knows everything. Tinntus my butt.
What about ‘Gypsy wagons’ only on still and soft summer afternoons in the country just around sundown? It was quite loud and distinctive; we had gravel roads but no-one when I was a boy would still have owned anything with solid wheels..
Here in Southern Oregon (where the “Hum” has been heard for decades), it sounds more like an idling jet engine on the tarmac. We have irrefutable evidence that it is being caused by military experimentation. The so-called “Program” is also being used to neurologically attack individuals, typically via the left-side (ie, left ear) auditory system, with noise, music, and conversation, frequently done in the evenings when one is trying to sleep.
After several years of experimentation, and the purchase of lab-quality instruments, we have documented (now approaching 14 terabytes) these attacks with recordings and instrument logs. The breakthrough for us, was using AI to “clean” the recordings of purposed noise and static, which allowed the conversations to be heard much more clearly.
Wow! That is very interesting!
Have you paid particular attention to the days & months leading-up to that fateful event in 2001?
Especially, the 24 hours before it, & after?
Did you clock huge, frantic activity of the hum during 24 hours ahead of that then, sudden utter stopping of hum for about 24 hrs. before it restarted?
How about, the days & months ahead of the Shutdown?
I’m next door to a joint military base in WA. We had huge amounts of flights & range-practice for months ahead.
Then sudden utter quiet. Including no hum, right after the announcement & it sunk-in, & everyone got home stayed put.