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Creating at Cline Library

Your complete how-to guide for enjoying the Cline Library's MakerLab and multimedia Studios.



Acoustics - The science of the transmission of sound waves. Generally refers to the characteristics of auditoriums, theatres and studios with respect to their design.

Ambience - Room acoustics or natural reverberation.

Amplitude - The strength or level of sound pressure or voltage.

Analogue Recording - A means of recording audio whereby the recorded signal is a physical representation of the waveform of the original signal. Vinyl is an example of analogue recording.

Audio Frequency - Signals in the human audio range. Measured in Hertz (Hz).

Audio Interface - A device that has numerous audio inputs and outputs.

Background Noise - Noise from all sources unrelated to a particular sound that is the object of interest. Background noise may include airborne, structure borne, and instrument noise.

Bass - The lower range of audible frequencies (60-250Hz).

Bidirectional Microphone - A microphone that picks up equally from two opposite directions. The angle of best rejection is 90 deg. from the front (or rear) of the microphone, that is, directly at the sides.

Boost - To increase, make louder or brighter; opposite of attenuate.

Cardioid Microphone - A unidirectional microphone with moderately wide front pickup (131 deg.). Angle of best rejection is 180 deg. from the front of the microphone, that is, directly at the rear.

Clipping - Refers to a type of distortion that occurs when an amplifier is driven into an overload condition. Usually the "clipped" waveform contains an excess of high-frequency energy. The sound becomes hard and edgy.

Compression - The reduction of a span of amplitudes done for the purpose of limiting the reproduction of those amplitudes.

Condenser Microphone - A microphone that generates an electrical signal when sound waves vary the spacing between two charged surfaces: the diaphragm and the backplate.

DAW (Digital Audio Workstation) - A computer-based recording and editing machine used for manipulating sounds.

Decibel (dB) - A number used to express relative output sensitivity. It is a logarithmic ratio.

Diaphragm - The thin membrane in a microphone which moves in response to sound waves.

Digital - A reference to a system whereby a continuously variable analog signal is reduced and encoded into discrete binary bits that establish a mathematical model of an original signal or other information.

Directional Microphone - A microphone that detects and transmits sound from only a certain direction.

Distortion - Anything that alters the musical signal. There are many forms of distortion, some of which are more audible than others.

Echo - Reflection of sound that is delayed long enough (more than about 50 msec.) to be heard as a distinct repetition of the original sound.

Equalizer - Audio device with multiple frequency controls for adjusting sound tone quality.

Equalization - Equalization or tone control to shape frequency response in some desired way.

Feedback - Feedback occurs when a sound loop exists between an audio input, for example, a microphone, and an audio output for example, a loudspeaker entering the microphone and being re-amplified.

Filter - A type of powerful tone-shaping network used by synthesisers to create tonal sweeps and changes.

Frequency - The number of times a signal vibrates each second as expressed in cycles per second (cps) or Hertz (Hz).The higher the frequency the higher the pitch.

Gain - The ratio of the signal level at the output of an audio device to the signal level at its input. Expressed in decibels (dB).

Harmonic - Frequency components above the fundamental of a complex waveform. They are generally multiples of the fundamental which establish the timbre or tone of the note.

Headroom - The ability of an amp to go beyond its rated power for short durations in order to reproduce musical peaks without distortion. This capability is often dependent on the power supply used in the design.

Hertz (Hz) - Unit for measuring frequency of d signal; formerly called "cycles per second."

High-Pass Filter - An electronic filter used in various audio circuits to attenuate all frequencies below a chosen frequency.

Hypercardioid - A hypercardiod is a unidirectional microphone with tighter front pickup (105 deg.) than a supercardioid, but with more rear pickup. Angle of best rejection is about 110 deg. from the front of the microphone.

Interference - Destructive combining of sound waves or electrical signals due to phase differences. - States that direct sound levels increase (or decrease) by an amount proportional to the square of the change in distance.

Latency - Delay that occurs between a MIDI keyboard being played and the sound appearing at the output soundcard or interface.

Level - The ratio of an acoustic quantity to a reference quantity. A measurement of amplitude in decibels.

Loudness - A subjective term for the sensation of the magnitude of sound. The subjective response to a sound level.

Low Frequency - The lower range of audible frequencies.

Microphone - An acoustical-electrical transducer by which sound waves in air may be converted to electrical signals.

MIDI - Musical Instrument Digital Interface. A machine protocol that allows synthesizers, computers, drum machines and other processors to communicate with and/or control one another.

Mixer - A mixer is a device that allows several different audio sources to be combined. It provides independent control over each signal's loudness, tone and stereo position.

Modulation - The process of sending a control signal to a sound source so as to change the character of the sound.

Noise Canceling - A microphone that rejects ambient or distant sound.

Octave - An octave is a doubling or halving of frequency. 20Hz-40Hz is often considered the bottom octave. Each octave you add on the bottom requires that your speakers move four times as much air.

Omnidirectional Microphone - A microphone that picks up sound equally well from all directions.

Phasing - The hollow sound that occurs when two identical waves combine.

Pitch - The fundamental or basic frequency of a musical note.

Pop Filter/Shield - An acoustically transparent shield around a microphone cartridge that reduces popping sounds. Often a ball-shaped grille, foam cover or fabric barrier.

Pop - A thump of explosive breath sound produced when a puff of air from the mouth strikes the microphone diaphragm. Occurs most often with “ p,” “t,” and “b” sounds.

Refraction - The bending of sound waves by a change in the density of the transmission medium, such as temperature gradients in air due to wind.

Reverberation - The reflection of a sound a sufficient number of times that it becomes non-directional and persists for some time after the source has stopped. The amount of reverberation depends on the relative amount of sound reflection and absorption in the room.

Rhythm - The regular or ordered repetition of dominant and subordinate elements within music.

Sensitivity - The electrical output that a microphone produces for a given sound pressure level.

Sequencer - A program that records and plays back user-determined sets of audio and MIDI data. Most sequencers also allow the data to be edited in various ways, and stored on disk.

Sibilance - An exaggerated hissing in voice patterns.

Sound ProofingBuilding materials that makes structures impervious to sound or insulates against sound.

Spectrum -The distribution of energy as a function of frequency for a particular sound source.

Subwoofer - A speaker designed exclusively for low-frequency reproduction. A true subwoofer should be able to at least reach into the bottom octave (20-40Hz). There are many "subwoofers" on the market that would be more accurately termed "woofers".

Super Cardioid Microphone - A unidirectional microphone with tighter front pickup angle (115 deg.) than a cardioid , but with some rear pickup. Angle of best rejection is 126 deg. from the front of the microphone, that is, 54 deg. from the rear.

Tempo (Italian for "time")Tempo is the speed or pace of a given piece.

Timbre - The characteristic tone of a voice or instrument; a function of harmonics.

Transducer - A device that converts one form of energy to another. A microphone transducer (cartridge) converts acoustical energy (sound) into electrical energy (the audio signal).

Treble - The highest part, voice, instrument, or range.

Tone - A tone results in an auditory sensation of pitch.

Unidirectional Microphone - A microphone that is most sensitive to sound coming from a single direction-in front of the microphone. Cardioid, supercardioid, and hypercardioid microphones are examples of unidirectional microphones.

Vibrato - Pitch modulation performed by an LFO to control a VCO.

Wave - A regular variation in electrical signal level or sound pressure level.

Waveform - A graphic representation of the shape of a sound wave. The waveform determines some of the physical characteristics of the sound.

Wavelength - The physical distance between the start and end of one cycle of a soundwave.

XLR - One of several varieties of sound connectors having three or more conductors plus an outer shell which shields the connectors and locks the connectors into place

X-Y Pattern - A pair of cardioid microphones or elements aimed in crossed directions which feed two channels for stereo pickup.