In hearing, the threshold of pain is the sound pressure or sound pressure level beyond which sound becomes unbearable for a human listener. This threshold varies only slightly with frequency.Different values for the threshold of pain are found in the literature: The volume in acoustics refers to loudness. It is a common term for the amplitude of sound, the sound pressure or the sound pressure level. Prolonged exposure to sound pressure levels in excess of the threshold of pain can cause physical damage, potentially leading to hearing impairment.
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