Schumann Resonance: What 7.83 Hz Actually Is, Why You Can’t Hear It, and What the Research Really Studied

The Schumann resonance is the 7.83 Hz often called “the Earth’s heartbeat.” But it is an electromagnetic phenomenon, not a sound, and 7.83 Hz is too low for human ears. This article checks what 7.83 Hz actually is with a few calculations, describes what happened when this channel made a 7.83 Hz track, and summarizes what research has actually examined, as far as it could be verified.

What 7.83 Hz is (by calculation)

Somewhere on Earth, lightning strikes dozens of times every second. Its electromagnetic waves travel around the planet between two “walls,” the ground and the ionosphere, and the waves whose length matches one trip around the Earth reinforce each other. That is the Schumann resonance, and it is why its wavelength is almost exactly the Earth’s circumference.

Prediction and observation

In 1952 the German physicist Winfried Otto Schumann showed theoretically that electromagnetic waves should resonate in this cavity. The first report of the resonances actually being observed was Balser and Wagner in 1960 (Balser & Wagner 1960, Nature).

For an ideal, lossless cavity the resonant frequencies work out as below. The real Earth–ionosphere cavity loses energy, so the observed values are lower: the lowest is about 7.8 Hz, followed by modes around 14 Hz, around 20 Hz, and so on.

Why you cannot hear it

The Schumann resonance is not a vibration of air, so it is not something ears can hear in the first place. And even if you played 7.83 Hz as an air vibration (a sound), it would be below the roughly 20 Hz lower limit of human hearing.

So in this channel’s one-hour 7.83 Hz track, 7.83 Hz is represented as a pulse: a low sustained tone at 174 Hz whose volume swells very slightly 7.83 times per second. The first version put almost all of its sound below 400 Hz; on phone speakers it was nearly silent and the pulse never arrived. The measurements and the fix are in the production note.

What research has examined

There are studies connecting the Schumann resonance with the body, but they are not about sound.

• An experiment applying very weak 7.8 Hz, 90 nT magnetic fields to rat heart-muscle cell cultures (Elhalel et al. 2019, Scientific Reports).
• A randomized controlled trial in people with insomnia using a device that emits an electromagnetic field at Schumann resonance frequencies (Huang et al. 2022, Nature and Science of Sleep).
• A statistical comparison of the shapes of human EEG spectra and Schumann resonance spectra (Saroka et al. 2016, PLOS ONE).

All of these deal with electromagnetic fields or brainwave data, not with listening to a 7.83 Hz sound or volume pulse. This channel’s track represents the number 7.83 in sound; it does not reproduce the conditions of these studies. You may also read online that “the Schumann resonance is rising”; this article does not cover that claim, because no verified data was found for it.

For listeners

• A 7.83 Hz track is built from low tones. Phone speakers play very little of it, so use earphones or headphones.
• To see how low your own setup goes, play tones upward from 20 Hz in the Frequency Lab.
• This article does not promise any physical or mental effect. If you have health concerns, please see a doctor.

Frequently asked questions

Is the Schumann resonance a sound?

No. It is a resonance of electromagnetic waves, not a vibration of air.

If I play a 7.83 Hz tone, is that the same thing?

No. The number is the same, but electromagnetic waves and sound are different things, and a 7.83 Hz tone is inaudible to humans anyway.

How is it measured?

With low-frequency magnetic sensors or antennas placed away from electrical noise, recording the field’s fluctuations over long periods.

Is it always exactly 7.83 Hz?

No. It shifts slightly with the state of the ionosphere; 7.83 Hz is a representative value.