A measure of the loudness or intensity of a sound. The term actually stands for one tenth of a bel, the larger and less frequently used unit. The decibel is a tenfold logarithm to the base 10 of the ratio between two amounts of power and described by...

n. (dB) The standard scientific unit for expressing the intensity of a sound. Strictly, the decibel scale does not express the absolute intensity of a sound, but only the ratio between its intensity and some reference intensity. In practice, the...

(dB) A unit of physical intensity most commonly applied to sound stimuli though it can also be used to describe the intensity of other physical stimuli, such as light. A bel (named after Alexander Graham Bell, the inventor of the telephone, though...

Sound pressure level. The reference pressure is 20 micropascals, corresponding to the normal threshold of hearing at about 1000 Hz. This value is 0 dB. The audible range covers about 120 dB and the scale is logarithmic. Weighting schemes have been...

The decibel (dB) is a logarithmic unit of measurement that expresses the magnitude of a physical quantity (usually power or intensity) relative to a specified or implied reference level. Its logarithmic nature allows very large or very small ratios to...