gain

7.22  gain. Amount of amplification provided between the input signal and the output signal of a system. The parameter for which the gain is being specified, i.e., time-mean-square sound pressure, sound power, electrical voltage, or electrical power, should be stated.

Annotation         Gain is often expressed in decibels as equal to ten times the logarithm to the base ten of the ratio of time-mean-square output voltage or output sound pressure to time-mean-square input voltage or input sound pressure, respectively.