3-to-1 Rule

When numerous microphones are in use, be sure that each microphone is placed at least 3 times the width from one another in relation to their designated source of sound.

Automatic Mixer

These mixers turn off microphone channels that are not being used, and turn on channels that need to be activated, all without any interference from the user.

Boundary/Surface Microphone

Microphones that are specifically constructed to sit atop surfaces that reflect sound.

Cardioid Microphone

With a slightly wide front pickup (131 degrees), these unidirectional microphones offer an angle of best rejection at 180 degrees precisely from its rear.

Close Pickup

The act of placing a microphone at least 2 feet from its original source of sound.


A piece of equipment that can change and influence levels of signal.

Condenser Microphone

Microphones that produce an electrical charge when waves alter the balance between the charged diaphragm and the back plate.

Decibel (dB)

A logarithmic ratio, decibels are numeric digits used to measure a sounds intensity.

Delay (echo)

Sound that is reflected, then postponed to a point that it becomes a noticeable recurrence of the primary sound source.

Dynamic Microphone

Microphones that produce an electrical charge after a sound wave makes a conductor resonate within a magnetic field. Moving-coil mics consist of conductors made of coiled wire that’s connected to a diaphragm.


The lifting or lowering of a frequency response through the control of tone and equalization.


The wailing and shrieking sound that comes from a PA system containing a microphone, amp and loudspeaker. This happens when already amplified sound from a speaker moves into a microphone, then re-amplifies.

Flat Response

A response of frequency that, at all frequencies, is equally balanced.


Normally measured in Hertz (Hz), “frequency” is the rate of how often something occurs, notably a sound wave.

Frequency Response

A graph that explains how a microphone reacts to different frequencies of sound.Typically measured in decibels versus frequency (in Hertz).


The intensification of a sound level or voltage, causing it to become amplified.


The level of gain that can be reached before feedback becomes noticeable in the sound system.

Headworn Microphone

A hands-free microphone, specifically made to be worn on the head. Hertz (Hz)–A unit of frequency that is measured in cycles-per-second. In musical terms, the “A” note above middle “C” is equal to 440 Hz.


A measurement in ohms of the opposing flow in an electrical current. Microphones with high impedance have at least 10,000 ohms, while microphones with low impedance have between 50 and 600 ohms.

Lavalier Microphone

A tiny, hands-free microphone that is typically attached to clothing. Leakage–The unintentional pickup of an instrument through a microphone that was specifically set up for another instrument.

Multi-track Recording

A recording style that involves each instrument recorded separately to their own individual tracks, then later mixed together in stereo. Recordings involving 4, 8, 16 and 24 tracks are quite commonly used.

Omnidirectional Microphone

A microphone designed to gather sound equally from its surroundings.

Overhead Microphone

Normally hung from the ceiling, these microphones are commonly used to pick up group vocals and many instruments all at once.


A sound distribution system that stands for “Public Address”.

Phantom Power

A technique designed to provide power through a cable to a condenser microphone.


The resonance of a sound that turns into an echo-like force and continues to be heard, even after the original source has come to a halt.


The output of electricity that comes from a microphone for a specific level of sound pressure.

Shaped Response

A response of frequency that shows a clear alteration within its area from flat.

Shotgun Microphone

A microphone that’s remarkably directional, used quite often in film productions and broadcast.

Sound Reinforcement

The boost in volume of a live sound source.


Audio that comes from separate right and left channels, meant to create a surrounding effect for the listener.

Supercardioid Microphone

A microphone that’s unidirectional, contains minimal rear pickup, but consists of a tighter front pick up angle (115 degrees) than a typical cardioid mic. For greatest rejection, place the angle at 126 degrees from the microphones front, which from the rear, would be at a 54 degree angle.

Unidirectional Microphone

A microphonethat is most receptive to the sound coming directly in front of it. Examples of unidirectional microphones include both cardioid and supercardioid microphones.