Some of our best videos aren't really that visual.
They're recordings of strange sounds that defy explanation.
And this one will leave your head ringing.
January, 2017, Dillon Dickerson is taking out the trash
from his home in Lewisburg, North Carolina
when a loud noise startles him.
He grabs his smartphone and records this.
[horn-like sound]
The video shows Dillon's backyard-- nothing special,
except for that consistent, blaring sound
piercing the suburban quiet.
[horn-like sound]
It sounds like the source must be nearby,
but there's nothing in sight.
We reached out to Dillon, who says the sound
was very real and very scary.
DILLON DICKERSON: It sent chills down my spine.
I felt very in shock.
I didn't really know what to think.
NARRATOR: Dylan says he later searched
for the source of the sound, but never found it.
And after he posted the video online--
DILLON DICKERSON: People came up with so many theories,
like it's apocalyptic signs or machinery
or factories in the background.
NARRATOR: The apocalyptic theory Dillon mentions comes
from the Bible, according to Professor of Religious
Studies Diana Pasulka.
DIANA PASULKA: According to the revelation of John
in the Bible, the Book of Revelations, the apocalypse,
or the end times, are going to be heralded by these
trumpets-- the trumpets of revelation.
NARRATOR: But journalist Alexis Brooks suggests another theory.
What if the sound is part of a secret program?
The US government has previously used
high-frequency pulses to study the Earth's upper atmosphere.
But many believe these sounds can be used
to cause floods and hurricanes.
Others say they can down planes and cause chronic fatigue.
ALEXIS BROOKS: Some people feel that advanced technology
is being used to puncture and literally shift the ionosphere.
Some feel that the weather is being controlled and perhaps
used for nefarious purposes.
So here's an interesting fact.
The Air Force actually did try to manipulate the weather
during the Vietnam War through a secret cloud-seeding program
called Operation Popeye.
So what's the source of this strange sound--
a government experiment, the supernatural,
something else entirely?
We sent the video to our audio expert,
Dr. Ben Gottesman, who created a spectrogram
to visualize the sound.
[horn-like sound]
As you can see, there's seven major episodes
where they flare up.
NARRATOR: First question-- could this
have been some kind of weather or atmospheric phenomenon?
BEN GOTTESMAN: There's a whole spectrum
of different types of thunder, from loud bangs to low rumbles.
NARRATOR: But listen to thunder--
[thunder rumbles]
--compared to Dylan's noise.
[horn-like sound]
Doesn't sound like a match.
BEN GOTTESMAN: Thunder really doesn't produce
these sorts of harmonics.
It's much more of a lower, cacophonous rumble.
NARRATOR: Gottesman believes the most likely
source is something mechanical.
BEN GOTTESMAN: When the brakes of semi-trucks go bad,
they can sometimes produce this long,
drawn-out screeching sound, similar to what
we hear on this recording.
NARRATOR: Gottesman compared Dylan's sounds
with some squeaky brakes.
[screeching]
BEN GOTTESMAN: So that's the truck brake.
Most of the energy the strongest is at 260 hertz.
And here, it's also--
the strongest is around 260, right here.
It's good evidence that it's some mechanical sound
because there are certain shared characteristics--
the harmonics, the tonal structure.
NARRATOR: While Gottesman see similarities,
there's something that still doesn't add up.
BEN GOTTESMAN: These were really ominous and strange-sounding,
so I wouldn't expect one truck to produce what was recorded.
NARRATOR: The sound from Dylan's yard
seems to be from multiple vehicles layered together.
[horn-like sound]
So is it proof or not?
Dillon swears the video hasn't been doctored,
and he's captured similar sound since.
And according to our expert, it's not the weather,
and it's likely not end times.
The truck brakes theory is interesting,
but we can't explain the layering or why
the sound went on so long.
This case remains a mystery.
Our verdict?
Unidentified sound.
They're hearing it in Rochester, New York.
[humming]
I want to locate it to stop it.
NARRATOR: They're hearing it in Bristol, England.
[humming]
And in Connecticut, Steve Kohlhase is
even hearing it in his bedroom.
It's a droning sound, and it's a lot worse at night.
It's impossible to live with it.
NARRATOR: Listen closely.
[humming]
Around the world, people are reporting
a low, incessant, highly disturbing hum.
Steve says he's been hearing it since 2009.
And as you can see on this website dedicated to hum
reports, he's one of thousands.
There's a developing map that people self-populate,
and it's quite a large community.
MJ BANIAS: The hum is a worldwide phenomenon of
this strange, mysterious sound.
NARRATOR: Journalist MJ Banias says
the mystery is complicated because the hum
is not always the same.
The hum changes.
It's not one unified sound across the planet
or in different areas.
NARRATOR: That's led to a wide range of theories.
Banias, who specializes in the unexplained,
says many involve a vast system of secret tunnels.
One pretty wild internet conspiracy theory
is that there exists a breakaway civilization, a group of humans
who are much more advanced than we are digging under the Earth
so that they can build cities under the Earth's surface.
NARRATOR: Others believe the US government is building
a network of tunnels using shuttered Walmarts as entry
points and supply stations.
The US government digging underground tunnels
would most likely have to do with stockpiling weapons
or supplies, nuclear bombs.
Here's another weird thing about the hum.
Only certain people hear it.
We've enhanced the best recording we have
so you can hear it come through your screen.
[humming]
But we've got questions about its source and its victims.
We turn for answers about strange sounds
to our audio expert, Dr. Ben Gottesman.
The hum is an amazing, sonic mystery.
Gottesman is interested in a theory
proposed by hum sufferer Steve Kohlhase,
a mechanical engineer.
He traces the hum to natural gas pipelines.
STEVE KOHLHASE: This is a map that I
prepared to find a correlation to pipeline location
and hum reports.
And within 95% accuracy, this does such a thing.
BEN GOTTESMAN: But other people in this field will say,
there have been occurrences far from gas plants.
NARRATOR: So we have Gottesman do a spectrogram of our best
hum sound, the one out of Rochester,
to see if he could place it.
[humming]
BEN GOTTESMAN: It seems like the hum is distinctly
different from traffic.
[engine sound]
[humming]
We know it's this continuous hum.
NARRATOR: The continuous nature of the sound
also rules out weather events, which clearly begin and end.
As for the tunnel theory--
BEN GOTTESMAN: Most of these seismic vibrations
within the Earth are much lower frequency
than what humans can detect.
If you're digging a tunnel underground,
I'd be hard-pressed that humans can hear it at all.
NARRATOR: Gottesman compares the Rochester
hum to several possible matches with no luck,
until he finds this.
[buzzing]
--an air vent.
Compare that to the enhanced hum.
[humming]
It's curious to me that it's really a similar frequency
to this ventilation fan.
NARRATOR: That might explain this hum.
But Ben says it doesn't explain all hums
or why only some people hear them.
The answer, he says, is that some people might have
a kind of superhuman hearing that makes
the modern world extra noisy.
Hyperacusis is basically an extreme sensitivity
to certain frequencies, certain noises.
There could be people within a population
that, for sounds people could care less about,
for them it causes extreme annoyance or pain.
So it seems that the source of the hum
can be anything from a gas pipeline to an air vent.
But what makes it so disturbing to some hum sufferers?
Our verdict-- that rare condition called hyperacusis.
February, 2015.
At first glance, it looks like a totally overcast
day in Nuevo Laredo, Mexico.
But turn up the volume, and it sounds like anything but.
[groaning sound]
Musician Axel Samano is visiting a friend when she notices
the eerie, atmospheric noises and aims
her lens to search for the source, but with no luck.
[groaning sound]
The sound resembles a metallic moaning of some sort.
It lasts for approximately 8 seconds
and reaches a slight crescendo halfway
through, almost as if something is crying out in pain.
[groaning sound]
AXEL SAMANO: The sound was like metal bending.
When I realized that sound was coming from the sky,
I really got scared because I didn't know what it was.
[groaning sound]
NARRATOR: Catholic miracle researcher Michael O'Neill
reminds us that strange sounds from the sky
are often read as signs of pending apocalypse.
But so far, the world hasn't ended.
Throughout human history, there
have been these reports of booming sounds
or large screeching sounds or this moaning sound,
as we hear in Mexico.
This is nothing new.
People have experienced and reported this in countries
all over the world for centuries.
[groaning sound]
NARRATOR: Others wonder of this mysterious sound
could be somehow tied to the legend of La Llorona,
or the weeping woman.
For centuries, Mexican children have
been raised to fear the wailing woman whose spirit is trapped
on Earth mourning two children she drowned
in a fit of jealous rage.
There have even been reports of strange encounters
with La Llorona amongst Spanish speakers all over the world.
Some of the strange sounds we've investigated
before could be explained.
This one turned out to be squeaky truck brakes.
[squeaking]
And this was a guy in Jersey with a homemade air cannon.
[explosion]
So does this moaning noise above Nuevo Laredo
have a common-sense explanation, or will it
remain an unexplained mystery?
Let's listen to our experts.
First, we bring the video to Professor of Atmospheric
Sciences Dr. Dianna Hence to determine if the sound could be
an aeolian tone, which is the sound produced by a strong wind
as it passes over or through a fixed object.
This singing, ringing tree sculpture
in Lancashire, England was designed
with this concept in mind.
[whistling]
I had some questions as to whether or not
this could be the wind interacting
with a particular structure or something
nearby that would result in this particular sound.
[groaning sound]
But the wind speeds were not very high--
about 15 miles per hour.
So unless that wind happened to be hitting
the resonant harmonic frequency of an object that would cause
that to happen, that doesn't really explain what's
going on very readily, either.
[groaning sound]
NARRATOR: Meteorology doesn't seem to hold the answer here.
So we bring the footage to our soundscape ecologist,
Dr. Ben Gottesman.
BEN GOTTESMAN: When I heard this mysterious Mexican moan sound,
I went digging and came across this one from Allen, Texas
from 2012.
[groaning sound]
NARRATOR: When Dr. Gottesman compares the recordings,
the similarity to the mysterious sound that
caused the sensation in Texas three years earlier
is undeniable.
[groaning sound]
Here's our sound, as you see, five events.
Now, let's look at this other video captured in Texas.
Again, we see these five events exactly the same,
which leads me to believe that there is some sort
of editing going on here.
[groaning sound]
And so we can say that it's likely
that whoever made this video used the audio
in the Allen, Texas video.
So our verdict, based on Dr. Gottesman's analysis--
we're calling this a hoax.
This is most likely just a prerecorded sound found
by somebody on the internet and repurposed
to create an online sensation.
The moaning has less to do with a cry for help
and more to do with a cry for attention.
It's April 2020 in the woods near Scranton, Pennsylvania.
Chase Floyd, a science teacher, is investigating
mysterious howling and whooping noises that he started
hearing the night before.
[whooping sound]
Chase continues to record as he explores the area.
He now suspects the noises he's hearing
were made by a Sasquatch.
[whooping sound]
Let's take a closer listen.
[whooping sound]
It sounds like a strange whooping noise.
As Chase seemingly moves closer to the source of the sound,
his breathing gets faster and more labored,
but he forges on anyway.
Right now, I'm starting to get lightheaded.
I really don't feel good right now.
As I kept going, I started feeling nauseous.
I got to a point where I was like,
I just kind of want to get out of here and lay down.
So I've done some research on unusual animal sounds.
So a lot of canines make weird noises,
but nothing that would make the sounds that are in the video,
at least not I know of in Pennsylvania.
NARRATOR: Once Chase shares the video,
it racks up over 600,000 views.
Field researcher Ken Gerhard says the animal sounds recorded
by Chase are all too familiar.
[whooping sound]
I've actually heard similar vocalizations,
and these are definitely attributed
to the Bigfoot phenomenon.
NARRATOR: What's more, Gerhard thinks Chase may be
experiencing ohmawing, a phenomenon
first described in Native American folklore
dating back two centuries.
Ohmawing is said to be an overwhelming energy
experienced in close proximity of a Sasquatch.
It manifests itself in a variety of symptoms,
including temporary paralysis.
I don't feel good.
So ohmawing is described as a type of infrasound.
The theory behind predators utilizing this infrasound
is that it is a way to disrupt, confuse, or disorient
their prey animals.
If Bigfoot actually exists, then ohmawing
may be a predatory mechanism.
Or maybe it's a defense mechanism like a skunk's odor.
So there are really two questions here, folks.
First, what made these sounds?
And second, is there anything to this theory of ohmawing?
Soundscape ecologist Ben Gottesman
breaks down the sound waves.
BEN GOTTESMAN: In order to find out what these alleged
sounds are, let's compare them to some
of the mammals in Pennsylvania.
NARRATOR: Gottesman starts with elk, which are known to produce
bugle calls like this.
[squealing]
[whooping sound]
BEN GOTTESMAN: It really isn't a match.
The frequency range doesn't match up.
The harmonic characteristics don't match up.
Up next, we have coyotes.
[barking]
[whooping sound]
The frequency range is much higher at around 650 hertz.
That's barely at the upper range of the alleged "whoop."
NARRATOR: Gottesman is unable to make any match.
But Professor of Biology Floyd Hayes
says that infrasound is for real.
And while humans can't hear it, they can feel it.
In fact, scientists believe tigers
can produce a roar under 20 hertz
below the human hearing range.
That has the power to stun or paralyze an animal.
Also, the lower the frequency, the farther the sound
can travel.
FLOYD HAYES: Infrasound is something
that several large species of animals can produce,
and some human vocalists are supposedly capable of producing
infrasound.
NARRATOR: But Hayes has a bone to pick with the idea
that Chase is suffering from ohmawing or any sort
of infrasound attack.
His behavior just doesn't make sense.
He's not feeling well.
He doesn't leave the area, and he
doesn't go to relax somewhere.
He still stays there and talks.
NARRATOR: After further analysis--
[whooping sound]
--Dr. Gottesman says that the sounds recorded by Chase Floyd
resemble another set of alleged Bigfoot recordings
he's analyzed for us in the past.
BEN GOTTESMAN: When I was listening to the alleged
sounds, I couldn't help but think back to Ron
Morehead's Sierra Sounds.
NARRATOR: He's referring to Ron Morehead's 1970s recordings
known as the Sierra Sounds, which many
consider genuine Bigfoot calls.
[whooping sound]
BEN GOTTESMAN: On top, we have audio from Ron
Morehead's Sierra Sounds.
I'm just going to play this series of three whoops,
and notice how the third one has a special flourish.
[whooping sound]
And now--
[whooping sound]
And if I ran a cross-correlation on these sounds,
they would be upwards of 99% similar.
It's the same sound, down to the tape
recording artifacts present in the Morehead tape.
This video is a hoax.
So while we can't rule out the possibility that ohmawing is
real and terrifying, it wasn't the cause
of Mr. Floyd's symptoms.
Our verdict-- this is a hoax.
These sounds are a copy of the alleged Bigfoot recordings
made in the early 1970s.