microphonelevel

Microphone level refers to the electrical signal level produced by a microphone before it is amplified. It is a very low-level signal that must be boosted by a microphone preamplifier to reach usable system levels for recording, mixing, or playback equipment. The term mic level is commonly used to distinguish this weak signal from higher-level signals such as line level.

Typical microphone level ranges are in the order of 1 to 10 millivolts, which corresponds roughly to −60 dBV to −40 dBV. In practical terms, this means microphone outputs are far smaller than professional line level, which is usually around +4 dBu (about 1.23 volts RMS) or consumer line level around −10 dBV (about 0.316 volts). The exact level depends on microphone type and distance from the source.

A microphone preamplifier increases mic level to line level, providing gain while preserving signal quality. Proper gain staging is important to minimize noise and avoid clipping. Many microphone inputs also supply phantom power (commonly 12–48 volts) to power condenser microphones; phantom power is not required by dynamic mics and should be used with care for ribbon microphones, depending on the model.

Impedance and connectivity play a role in microphone level chains. Mic preamps typically expect high-impedance, balanced connections to maximize noise rejection and preserve signal integrity. Input impedance is commonly in the kiloohm range, high enough to avoid loading most microphones.

In practice, microphone level is the starting point of most professional audio chains, with subsequent stages designed to bring the signal to line level and beyond for recording, processing, and distribution.