Understanding microphone sensitivity
For example, a microphone's sensitivity is -46dB(V)/Pa


-46 dBV is about 5 mV RMS and bear in mind we are talking about pure sinewaves at 1kHz (mid band). It's 5 mV because \$10^{\frac{-46}{20}}\$ = 5 mV.

This voltage arises from an SPL of 1 Pa RMS (unit of sound or any pressure in newtons per square metre) hence for 2 Pa RMS the output voltage will be 10 mV RMS. For 0.1 Pa the output will be 0.5 mV RMS.