Typical Mic Level Voltage

Mic outputs can range from very low to very high depending on the mic type and design.

Typical mic level voltage.

Of the four main types of audio signals mic level is the weakest and requires a pre amplifier to bring it up to line level. Most professional mics have an output impedance between 150 to 250ω source. Radio mikes are all over the place on impedance but frequently 600 ohms. Pc speakers and mics are generally very low impedance like 4 or 8 ohms.

0 dbv is an average line level typical output from rackmount guitar bass preamps. Audio level summary there are three main audio signal levels. The magnitude of the analog or digital output signal from the microphone with that input stimulus is a measure of its sensitivity. They make cheap audio transformers for just such a purpose plus they are useful for my next point.

A mic level or microphone level signal is the voltage level that comes out of a microphone when someone speaks into it typically just a few ten thousandths of a volt. 30 dbu is again in the neighborhood of a typical microphone or di box s output. Microphone levelis usually specified between 60 and 40 dbu. Dbu and dbv are decibel measurements relative to voltage several different types of devices are used to boost microphone levels to line level signals.

Microphone sensitivity is typically measured with a 1 khz sine wave at a 94 db sound pressure level spl or 1 pascal pa pressure. Mic level microphones have comparatively small output voltages on the order of thousandths of a volt 0 001v ranging up to tenths of a volt 0 1v. 10 dbv is consumer line level common with older and cheaper recording gear. Mic level millivolts line level around 1 volt and speaker level around 10 volts or more.

Levels can vary between 2mv 0 002 volt to as much as 1v or more depending on how loud the source is and how sensitive the mic is. Microphone level is in the region of 60 dbv 0 001 volt to 40 dbv 0 010 volt. 20 dbu is roughly in the neighborhood of a typical instrument s output.