DB
A logarithmic ratio of audible signal strengths between two sounds or two levels of the same sound. In other words, it is the unit of measure used to express differences in loudness. For every 3 dB, the loudness changes by a factor of 2: -3 dB is half as loud, +3 dB is twice as loud . A 1 dB change in sound level is just detectable by the human ear.
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