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And to go even further down the digression rabbit hole...
The bel (named for Alexander Graham Bell) is a base-10 logarithmic unit for measuring ratios. The decibel (dB, tenth of a bel) is a convenient unit of measurement since 1 dB is approximately the just noticeable difference (JND) in sound intensity for a normal person. Changes in sound intensity of less than 1 dB are imperceptible.
When discussing dB in audio you need to take into account whether you are referring to voltage or power (sound intensity). A CD uses 16-bit samples, which indicate the voltage of the signal. Adding a bit doubles the number of possible voltage levels. This is a log10(2)=0.3 bel (3 dB) increase. However, power increases with the square of voltage (for a fixed load resistance) which means that dB of sound intensity are double dB of voltage, or 6 dB per bit.
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