Audio Signal Levels: General Guidelines

Date Updated: August 31, 2017
Question:
I have heard the terms: mic level; line level; aux level. Please provide details.
Answer:


Here are general guidelines to the typical ranges of audio signal levels.  Note the difference between each defined signal level range is 20 dB.
Mic level signal (low) = 0.0001 V = 0.1 mV = -80dBV
Shure SM11 output is an example.
Mic level signal (average or typical) = 0.001 V = 1 mV = -60 dBV
Shure SM58 output is an example.
Mic level signal (high or "hot") = 0.01 V = 10 mV = -40 dBV
Shure MX418 output is an example.  Also the Shure 588SDX output, set to high impedance, is an example.
Auxiliary level signal (AUX) = 0.1 V = 100 mV = -20 dBV
Shure SCM268 output, RCA jack, is an example.
Line level signal = 1.0V = 1,000 mV = 0 dBV
Shure SCM810 main output is an example.
Power amplifier signal (loudspeaker level) = 10V = +20dBV
QSC GX3 amplifier output is an example.