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Perception of Sound

  • Humans can detect sounds ranging from 20 Hz to 20 kHz, but this varies with age, sex and environmental factors.
    As people get older, their ability to detect higher frequencies decreases, especially if they have been exposed to prolonged periods of loud noise.
    Females can often perceive higher frequencies better, while males can often perceive lower frequencies better.
  • Sound with a frequency below 20 Hz is known as infrasound.
    Sound with a frequency above 20 kHz is known as ultrasound.
  • Many animals can detect frequencies outside the human range of hearing.
    Examples
    • Elephants and whales can generate and detect infrasound frequencies which they use for long-distance communication.
    • Dogs and cats can detect ultrasound frequencies.
    • Bats use very high frequency ultrasound for echolocation – by bouncing these sound waves off objects they can ‘see’ in the dark.

 
ultrasound frequency bat echolocation

Bats use sound frequencies well above the range of human hearing to detect objects in darkness.

(Image: Shung, Wikimedia Commons)

 

(Header image: Thaut Images, Adobe Stock)