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How does the ear’s dynamic range extend from the threshold of hearing to the threshold of pain?

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Watch a suspended vibrating spring to learn about the propagation of sound waves — sound Learn about the propagation of sound waves from a point source by observing the motion of a suspended vibrating spring.

The human ear possesses an extraordinary dynamic range, spanning from the threshold of hearing—the quietest sound detectable—to the threshold of pain, where sound becomes physically uncomfortable. This range covers an intensity difference of 12 orders of magnitude, meaning the threshold of pain is one trillion times more intense than the threshold of hearing.12

Because of this vast range, the ear’s response to intensity is nonlinear and logarithmic. Rather than responding to absolute changes in pressure, the ear responds to ratios, allowing it to remain sensitive to extremely faint sounds while also processing intense waves.2

This logarithmic nature is reflected in the decibel scale, where the smallest detectable change in intensity—the just noticeable difference—is approximately one decibel. As sound intensity increases, the basilar membrane within the cochlea vibrates with greater amplitude, stimulating more hair cells and increasing the rate of nerve impulses sent to the brain.23