device for measuring the intensity of noise, music, and other sounds. A typical meter consists of a microphone (q.v.) for picking up the sound and converting it into an electrical signal, followed by electronic circuitry for operating on this signal so that the desired characteristics can be measured. The indicating device is usually a meter calibrated to read the sound level in decibels (db), a logarithmic unit used to measure the sound intensity (q.v.). Threshold of hearing is about zero decibels for the average young listener, and threshold of pain (extremely loud sounds) is around 120 decibels, representing a power 1,000,000,000,000 (or 1012) times greater than zero decibels.
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