Everything on this earth vibrates, including humans which resonate at a frequency between 5 and 10 hertz.
So given all things that have a frequency produce a sound, what are those sounds?
Musician and TV presenter Richard Mainwaring explores that question in his new book Everybody Hertz: The Amazing World of Frequency, from Bad Vibes to Good Vibrations.
Photo: Supplied
Listen to the full interview
The tale of the lonely whale is one of Mainwaring's favourite frequency stories.
“[This one whale] was singing at the wrong frequency; no other whale was singing at this frequency of 52 hertz. And it just kind of wandered around the ocean, singing at 52 hertz, with every other whale saying 'that is lovely, but I have no idea what you're talking about."
This is because there are two types of frequency, he tells Kathryn Ryan.
“There's a kind of sound frequency and there's another one which is much more complicated called an electromagnetic frequency.”
Sound is created by air being pushed forward, he says.
“If I went 'boo' I kind of push the air forward as I make that sound, the air is pushed forward and then it bounces back, it's a bit like jelly.
“So, it goes forward, back and it goes back to its original place so if the air went forward and back and back to its original place once in a second, that would be 1 hertz.”
The standard musical note of A has an audio frequency of 440 hertz, he says.
“If I take an A, which the oboe plays when the orchestra tunes, that is 440 hertz. So that means the air is wobbling back and forth 440 times per second.”
A much lower sound was detected by NASA scientists observing black holes from the Chandra X-ray telescope, Mainwaring says.
"There's this kind of torch-beam of relativistic plasma which comes out in a straight line out of a black hole. And this super-fast relativistic plasma hits this gas cloud, in the Perseus galaxy, and it makes the gas cloud wobble.”
The lower the frequency, the greater distance a sound wave can travel, he says, but this journey can be pretty slow.
“It takes 18.5 million years for [the gas cloud] to go forward and back. That's how long the shock wave takes. So, NASA said, that is the lowest note in the universe. And that is a B flat about 55 octaves down from the end of a piano. So that's the lowest note.”
Animals can detect much lower frequencies than humans, Mainwaring says.
“Elephants, and bizarrely ferrets - I don't quite get that - can hear much, much lower than we can. And they're also very good at feeling frequencies, as well.
“Elephants hear things through their feet. They emit really low sounds, down to about 10 hertz, that's 10 times a second.”
The Infinite Piano, created by Richard Mainwaring Photo: Supplied: Richard Mainwaring
In Everybody Hertz, Mainwaring tells the story of a UK scientist who was disbelieving when colleagues told him they suspected the lab was haunted by a ghost.
“People were saying I'm not staying up late at night, this place is haunted. I get the creeps and I get really weird feelings and the sweats.”
The scientist dismissed their reports as nonsense until one night he saw something himself.
“Out of his peripheral vision, he sees an apparition and he's absolutely freaked out. It's just on the edge of his vision, and this grey blob moves towards his vision, he looks at it, and it disappears.
“So, he's really freaked out by this. Now, what could this be?
"The following day, bizarrely, he's entering a fencing competition. He takes his sword into his lab, and he puts it in the vice in the middle of the room and he's going to clean it, gets some cleaning material and comes back.
"And this sword is vibrating back and forth really, really fast in his vice.”
The man eventually figured out that a sound wave, undetectable by humans, was behind the ghostly happenings.
“There's a sound wave going on in that room, which is bouncing off itself and making his sword vibrate back and forth.
"He works out that it's a faulty fan blade in his air conditioning system, the extractor fan.”
NASA scientists were already aware of this phenomenon, Mainwaring says.
“They found out a number of years before that your eyeballs vibrate and resonate at certain frequencies. Their astronauts were having real problems with their eyesight when the rockets were taking off, because of this thing called infrasound, which is beneath where we can hear.”
Very low frequencies can have a psychological effect on humans, he says.
“[They can give] you a real sense of doom-laden fear and you have sweats, you start to gag.”