Infrasound: The Unseen Wave That Moves Us

Acoustic waves below roughly 20 hertz are known as infrasound and can impact the body in uncomfortable ways./nInfrasound is below the threshold of human hearing and is felt on the body rather than heard./nThe lower the frequency of a sound, the longer the wavelength, making it harder to generate, control, and detect infrasound./nGenerating a clean waveform precisely at low frequencies like four to seven Hertz is challenging and often requires large speakers or frequency-tuned fans./nInfrasound is used in various settings including initial screenings of movies like the Exorcist for inducing stress.