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.
This chapter is dedicated to a subject which is often a little bit muddled, because there are many definitions associated to it and one always runs the risk of mistaking something for something else.
When several sound sources are combined, each of which generates a certain amount of dBspl, it isn't possible to simply sum up these values, but we should rather use the following empirical formula
Seeing that dB's produce perception of sound quantities by the human ear, the dB unit also expresses a series of electical quantities on a practical level.
By dynamic range we mean the interval, measured in dB (the dB varies depending upon the dynamics of the contexts we are dealing with), between the lowest value that an audio signal can have and its highest.
Generally they are built with a very sensitive microphone inside and they are calibrated so as to capt sound pressure with a response that mimes that of a human ear.
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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.
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