——— C ———

C – (1) The abbreviation for coulomb. (2) The symbol for capacitance. (3) The abbreviation for Celsius. (4) The abbreviation for chroma in Y/C-video.

C-12 – refers to the AKG C-12 microphone.

C 414 – refers to the AKG C 414 microphone.

cab – short for cabinet.

cabinet – (1) A loudspeaker enclosure in which speaker drivers, crossover circuits, and (sometimes) amplifiers are mounted. Also called a speaker cabinet or speaker enclosure. (2) An enclosure for the speaker system of an instrument amplifier that does not contain an amplifier. When the cabinet contains both the speaker and an amplifier, it is called a combo amp.

cabinet grand – a full-size upright piano with strings running vertically and soundboards as larger or larger than a grand piano.

cabinet resonance – the resonance exhibited by a loudspeaker enclosure. This resonance is undesirable as it may obscure or interfere with the desired sound from the speaker drivers. Because resonance cannot be eliminated, cabinets are designed so that it occurs at frequencies where resonance is less audible.

cabinet sim – see amplifier modeler.

cabinet simulator – see amplifier modeler.

cable – (1) An insulated wire, wires, optical fibers, or both having a protective covering and used for transmitting electricity or audio signals. There are basically four types of cables used in a recording studio: (a) ¼-inch TS (tip sleeve) unbalanced cable, typically used for instruments and patch cords; (b) ¼-inch TRS (tip-ring-sleeve) balanced cable, typically used for headphones; (c) XLR balanced cable, typically used with microphones; and (d) optical audio cable, used for transmitting digital audio. (2) Short for cable television.

cable assembly – (1) A cable constructed for a specific applications, usually having appropriate connectors for the application. (2) A wiring harness

cable harness – see wiring harness.

cable jacket – see jacket.

cable management – the process of organizing and controlling cables, using cable trays, hooks, cable ties, flexible tubing, and other devices.

cable sheath – see jacket.

cable television – see CATV.

cable tester – a type of continuity tester designed for testing audio cables, typically having connections for TRS, XLR, phono jack, and other types of connectors.

cable tie – a type of fastener, for binding together cables, wires, hoses, and other devices. Normally made of nylon, the tie has a narrow, flexible section with teeth that engage into the head to form a ratchet so that as the free end is pulled the tie tightens and does not loosen. Some cable ties have a tab that can be depressed to release the ratchet so that the tie can be loosened or removed. Also called a tie-wrap, hose tie, zap-strap, or zip tie.

cable tray – a rigid structure usually resembling a ladder used to support cables. The trays are usually open at the top to facilitate making changes.

cable TV – see CATV.

CAE number – a nine-digit international identification number previously assigned to songwriters and publishers by performing rights organizations (PROs). It since has been replaced by the IPI number. CAE stands for the French words Compositeur, Auteur, et Editeur (Composer, Author, and Publisher).

CAF – Core Audio Format.

CAGED system – a system for playing notes on a guitar fretboard using the fingering positions for the chords C, A, G, E, and D. If you convert the C chord into a barré chord, you get the “C shape.” You can play any chord higher up on the fretboard by playing the next shape in the sequence. The lowest notes of the desired shape always overlaps the previous shape. For example, if you want to play an A chord in a different location than an open A, you would use the next shape in the sequence, which would be the G shape.The lowest frets of the G shape (fret 2) overlap with notes from the A shape. Also called CAGED theory.

CAGED theory – CAGED system.

cajón – a six-sided, box-shaped percussion instrument, originally from Peru, played by slapping the sides usually with the hands, but sometimes with other devices such as sticks, brushes, or mallets. Pronounced “ka-hone,” it is Spanish for “box.”

Cakewalk, Inc. – a now defunct music production software company based in Boston, Massachusetts, best known for the digital audio workstation (DAW) SONAR. It was founded in 1987 by Greg Hendershott as Twelve Tone Systems, Inc. Its initial product was a MIDI sequencer called Cakewalk. Many users also called the company by that name, and in September 2008, Twelve Tone Systems officially changed the corporate name to Cakewalk, Inc. The sequencer was renamed to Cakewalk Pro, and later, when they added digital audio support, it became Cakewalk Pro Audio. Also in 2008, Roland Corporation purchased of a majority share of the company and changed the product name to Cakewalk by Roland. In 2009, Cakewalk introduced its new DAW, SONAR, which is now known as Cakewalk Sonar. Cakewalk was acquired by Gibson in 2013. Cakewalk, Inc. closed in 2017, the assets of Cakewalk were acquired by BandLab Technologies in 2018.

Cakewalk Sonar – a digital audio workstation (DAW), which began as a sequencer called Cakewalk, developed by Twelve Tone Systems, Inc., which later became Cakewalk, Inc. The sequencer was renamed to Cakewalk Pro, and later, when they added digital audio support, it became Cakewalk Pro Audio. Also in 2008, Roland Corporation purchased of a majority share of the company and changed the product name to Cakewalk by Roland. In 2009, Cakewalk introduced its new DAW, SONAR. Cakewalk, Inc. was acquired by Gibson in 2013. Cakewalk, Inc. closed in 2017. In 2018, Gibson sold the assets of Cakewalk to Singapore company BandLab Technologies, who renamed the DAW to Cakewalk by BandLab. The name was later changed to Cakewalk Sonar.

calibration – see alignment.

calibration microphone – see measurement microphone.

Calibration Standard Instruments (CSI) – a loudspeaker designer and manufacturer in Oakland, CA, founded by Edward M. Long, who also founded E. M Long Associates. Long owns the trademark for the term NearField™, although it has more or less come into common usage in recent years. Because of the trademark, the term direct field has been used as an alternative.

call and response – a part of a song in which a line is sung followed by an answer line.

CALM – Commercial Advertisement Loudness Mitigation Act.

Calrec Audio – a manufacturer of professional audio equipment that produces broadcast mixing consoles. It is headquartered in Nutclough Mill, Hebden Bridge, West Yorkshire, UK. Formed as a microphone manufacturer in 1964, it launched its first audio console in 1971. In 2014, it merged with DiGiCo and Allen & Heath to form Audiotonix.

camber – the curvature of the fingerboard, especially of guitars, mandolins, violins, and other string instruments, or the curvature of the bow. Also called radius.

camcorder – a portable, self-contained device, that combines a video camera with a video recorder, typically designed for the consumer market. The name is a combination of camera + recorder.

camera – device for recording still and moving visual images in the form of photographs, motion picture film, or video signals.

Canadian Broadcasting Corporation – the national public radio and television broadcasting system in Canada, founded in 1936. It is officially branded as CBC/Radio-Canada.

cancellation – see phase cancellation.

cancellation reflection – a sound wave that is reflected from a wall and interferes with the original wave producing destructive interference (phase cancellation).

canned – a slang term for pre-recorded, especially (a) music used on radio or television instead of live music, or (b) canned laughter used in place of a live audience. The origin of the term can be traced to the early days of recorded music when the phonograph used wax cylinders to record and playback music. Consumers called the cylinders “cans.”

Cannon connector – see XLR.

Cannon Electric Company – a manufacturer of connectors, cable assemblies, keypads, and other electric devices. It was founded in Los Angeles, CA, in 1915 by James H. Cannon. Cannon was instrumental in developing some of the first equipment for sound films in the early years of the movie industry. In the 1930s, Cannon developed connectors for the aircraft industries. The D-subminiature connector was developed for military and aerospace applications in the 1950s. Also in the 1950s, Cannon developed a connector for use in military communications equipment called the XLR, that went on to be used in professional recording studios. The XLR is sometimes called a “Cannon connector.” In 1963, Cannon became a division of ITT under the name of ITT Cannon. In 2007, ITT Cannon changed its name to ITT Interconnect Solutions.

Canon, Inc. – (Kyanon kabushiki-gaisha). A Japanese multinational company headquartered in Ota, Tokyo, Japan, that specializes in the manufacture of imaging and optical products, including cameras, camcorders, photocopiers, computer printers, and medical equipment.

cans – a slang term for headphones.

cantilever – a very small arm on which the stylus is attached and which is connected to the phonograph cartridge.

cap – short for capacitor.

capacitance (C) – the ability of a system to store an electric charge, usually measured in farads.

capacitive coupling – the transfer of energy within an electrical network by means of the capacitance between circuit nodes, either intentionally or accidentally. Capacitive coupling is typically achieved by placing a capacitor in series with the signal to be coupled. See also dc coupling and inductive coupling

capacitor – an electronic device consisting of two plates separated by an insulator (called a dielectric) that stores an electric charge in the form of an electrostatic field. The three main types are the electrolytic capacitor, the ceramic capacitor, and the film capacitor. Formerly called a condenser.

capacitor microphone – see condenser microphone.

Capitol Records – see EMI Group.

capo – a movable clamp-like bar that can be attached to the fingerboard of a fretted instrument to raise the pitch of the strings. Short for the Italian word capotasto, which means “head of fingerboard.”

capstan – a motor-driven spindle on a tape recorder that pulls the magnetic tape across the heads at a constant speed. See tape machine for diagram.

capsule – the device in a microphone that converts sound into electrical energy. In a condenser microphone it is the capacitor section (the assembly of fixed and movable plates), for a dynamic (moving-coil microphone) it is the diaphragm and magnet assembly, and for a ribbon microphone it is an aluminum ribbon and magnet assembly. Also called generating element or simply element for short.

capture – (1) To record audio or video. (2) To convert analog signals, such as those generated by an audio player or video camera, into a digital format that can be stored. Also called audio capture or video capture.

capture board – see capture card.

capture card – a circuit board (card) in a computer used to receive digital data, such as audio or video, from a source. Also called a capture board. A capture card for video is often called a video capture card while one for audio is usually called a sound card.

capture effect – the suppression of a weaker FM radio signal by a receiver when a stronger signal is at or near the same frequency.

carbon button microphone – see carbon microphone.

carbon microphone – a microphone that consists of a container (called a button) filled with granules of carbon. Sound waves striking the diaphragm change the pressure on the granules causing the electrical resistance to change which alters the current flowing through the carbon. Carbon microphones were used in early model telephones from about 1915 to 1920s. Although fairly suitable for the limited voice range of telephones, they had high noise levels due to the carbon particles striking the diaphragm. Western Electric improved the design introducing the double-button carbon microphone (also called a differential microphone), which had two carbon-filled button-like containers that kept the particles from moving around. This design not only had lower noise, but higher output, lower distortion and improved frequency response. It was widely used in radio broadcasting from 1921 to 1931, when ribbon and condenser microphones began to take over. Due to its poor frequency response and high noise levels, carbon microphones are rarely used today in professional audio situations. Also called a carbon button microphone, button microphone, and carbon transmitter.

carbon transmitter – see carbon microphone.

cardboard frequencies – see mud range.

cardioid microphone – a microphone with a cardioid pickup pattern.

cardioid pattern – a microphone pickup pattern with maximum pickup in the front, less pickup from the sides, and the lowest pickup from the back. It is called “cardioid” because the shape of the pattern resembles that of a valentine-shaped heart. It is one of several unidirectional patterns. See also polar pattern.

cardioid trapezium – see cardioid trapezoid.

cardioid trapezoid – a surround sound microphone technique especially designed for live pop music concerts, which do not require pickup of side reflections. It consists of four cardioid microphones facing backward, angled at 60° from one another, and 60 cm (2 ft) apart, in the shape of a trapezoid. It is effective for the pickup of both audience and ambience. Also called a Theile trapezoid or cardioid trapezium (British).

card reader – an electronic device that reads and transfers data from various portable memory storage devices, such as SD cards.

carrier – (1) An electromagnetic wave of a particular frequency that can be modulated in amplitude, frequency, or phase in order to transmit speech, music, images, or other signals via radio transmission. Also called a carrier frequency, carrier signal, or carrier wave. See also frequency modulation and amplitude modulation. (2) The audio signal in a vocoder that is acted upon (typically a guitar or synthesizer tone) while the modulating signal (usually a voice) is the characteristics that are applied to that audio signal (the carrier). (3)  Another name for tape base.

carrier frequency – see carrier.

carrier signal – see carrier.

carrier wave – see carrier.

cart – short for cartridge. See Fidelipac.

cart machine – broadcaster slang for a tape cartridge machine. See Fidelipac.

cartridge – (1) See tape cartridge, Fidelipac, 4-track cartridge, and 8-track cartridge. (2) See phonograph cartridge.

CAS – Cinema Audio Society.

cascade – to connect two mixers together so that they act as one. The exact method to do this depends on the type of mixer. One way is to send the outputs of the first mixer to an inputs of the second. Another way is use Firewire or USB cables to connect the two.

cascaded filter – a filter consisting of several individual filters connected in series, with the output of one filter providing the input to the next.

cassette – (1) A small flat case containing a long strip of magnetic recording tape onto which sound or video can be recorded and played back. The audio cassette was introduced by Philips in 1982, originally for use in dictation machines. As the fidelity improved, it began to be used for audio applications, first as blank casettes that could be recorded and later sold as pre-recorded music. Also called a compact cassette, Musicassette (MC), audio cassette, video cassette, or cassette tape. (2) Short for cassette player or video cassette recorder (VCR), machines used to record and playback audio or video using a cassette.

cassette deck – a tape deck for playing and recording audio cassette tapes. See cassette player and cassette recorder.

cassette duplication – see duplication, definition #2.

cassette player – a machine that is used to playback audio recorded on a cassette. They can be portable or designed for use in the home or automobile. Often they have recording capabilities, but not always. They were once quite common, but lost favor when the CD was introduced. See cassette recorder.

cassette recorder – a machine that is used to record and playback audio recorded on a cassette. They can be portable or designed for use in the home or automobile. They were once quite common, but lost favor when the CD was introduced. If they do not have recording capabilities, they are considered to be a cassette player

cassette tape – see cassette.

CAT – see Category wiring.

Cat 43 – see Dolby Cat 43.

catch groove – the widely spaced groove on the outer edge of a vinyl record designed to “catch” the stylus and guide it into the playback area of the record.

catch up mode – a feature of some DAWs, consoles, mixers, or MIDI controllers in which motorized faders do not begin to follow fader automation until the control point crosses the current fader position. After that the fader follows the automation in the normal manner. Also called pick up mode.

Category wiring – a system of wire grading developed by the EIA and TIA which specifies wiring and transmission characateristics. Some examples are CAT 3, CAT 5, and CAT 6, sometimes written as Cat 3, Cat 5, and Cat 6. For more information, see Wikipedia entry at TIA/EIA-568.

catgut – a material used for the strings of musical instruments, made of the dried twisted intestines of sheep, goats, horses, and other animals (but not cats). The word catgut is thought to have been derived from the word cattlegut or from kitgut where kit means fiddle, and the word kit having been confused with the word for a young cat. For a long time, catgut was the most common material for stringed instruments, but it has been generally replaced by other materials, such as steel or synthetic polymers.

cathode – (1) A negatively charged electrode. (2) In a vacuum tube, the cathode is the heated filament.

cathode follower – a vacuum tube triode in which the output is taken off the cathode instead of the plate. Usually the output voltage is the same as the input voltage, but there is a gain in current. The cathode follower has a high input impedance and a low output impedance, which is in-phase with the input. It is typically used for impedance matching.

cathode ray tube (CRT) – a vacuum tube in which a cathode emits a beam of high-energy electrons that are accelerated through a high-voltage anode and focused electrostatically or electromagnetically using a yoke onto a phosphorescent screen to produce a visible image. Before the advent of flat-screens, it was the primary method of creating displays for television receivers, computer monitors, oscilloscopes, and other devices.

cat's cradle shock mount – a type of microphone shock mount consisting of two elastic bands that pass through several clips that isolate the microphone body from the mic stand.

cat's whisker – (1) A stiff wire with one end contacting a crystal used to tune a crystal radio. (2) A wire that makes contact with a semiconductor. Also called a cat whisker.

cat's whisker receiver – see crystal radio.

CATV – Community Antenna Television. The broadband transmission of multiple television channels using coaxial cable. Also called cable television or cable TV.

Cauer filter – see elliptic filter.

CAV – (1) Constant Angular Velocity. (2) Component Analog Video. See component video.

CBR – Constant Bit Rate.

CBC – Canadian Broadcasting Corporation.

CBS – Columbia Broadcasting System. A US television and radio network owned by CBS Broadcasting, Inc., headquartered in New York City. CBS began as the the United Independent Broadcasters Inc., a network of 16 radio stations that was purchased by William S. Paley in 1928, and renamed the Columbia Broadcasting System. CBS entered the television network business in 1941. In 1974, it became known simply as CBS, Inc. The network was acquired by Westinghouse in 1995, renaming the corporate entity to the CBS Broadcasting, Inc., and eventually becoming the CBS Corporation. In 2000, CBS was taken over by Viacom, a compnay formed as a spin-off of CBS in 1971. In 2005, Viacom was split into two companies: the CBS Corporation, having broadcast television, radio and cable television and publishng assets, and a new Viacom, consisting of BET Networks, MTV Networks, and Paramount Pictures Corporation. CBS Corporation is controlled by Sumner Redstone through National Amusements, which also controls the current Viacom. CBS continues to operate the CBS Radio network.

CB System – see IECEE.

CC – Continuous Controller.

CCD – Content Creator Data.

CCIR – Comité consultatif international pour la radio (Consultative Committee on International Radio). An organization formed in 1927 to manage the international radio frequency spectrum and to develop standards for radio broadcast systems, primarily in Europe. In 1932 the CCIR merged with the International Telegraph Union (ITU) and several other organizations and became the International Telecommunication Union in 1934. In 1992, the CCIR became the ITU-R, the radiocommunications section of ITU.

CCIR curve – (1) A method for measuring noise using an equalization curve according to ITU-R BS.468-4. The standard was previously CCIR 468-4, but is now maintained by the ITU. It is used mainly in Europe, the UK, and former members of the British Empire. It is less commonly used in the US where A-weighting is primarily used. (2) The former name for the IEC curve, but this usage should be discouraged to avoid confusion with the noise measuring curve in definition #1.

C clef – a symbol indicating which line of the music staff represents the pitch of middle C. For C on the first line (bottom line) it becomes the soprano clef, for C on the second line, the mezzo-soprano clef, for C on the middle line, the alto clef, for C on the third line, the tenor clef, and for C on the fifth line (top), the baritone clef. All but the alto and tenor clefs are rarely used.

C curve – see C-weighting.

CD – Compact Disc.

CD24 – a special type of compact disc designed to be recorded and played by the Alesis MasterLink, using high resolution audio (HRA) at 24-bit and 96kHZ. A CD24 can also be played in a computer's CD-ROM drive because it uses standard CD-ROM protocols, and the audio files are in the AIFF format, readable by most audio software.

CD-4 – Compatible Discrete 4. No connection with the compact disc (CD). See quadradisc.

.cda – Compact Disc Audio. The file extension used on files on a Red Book Audio compact disc (CD), usually shown as “Track01.cda,” etc. These files are not audio files, but rather are files that point to the beginning of the actual audio file on the CD, similar to a shortcut file on a PC. If these files are simply copied to the computer, they will produce a useless file that cannot be played. The actual audio on the CD uses the stereo 16-bit 44.1-kHz LPCM (linear pulse code modulation) audio format. These files can be converted to .wav files that can be played on the computer using a third-party utility, such as iTunes, EAC (Exact Audio Copy), or dB Power Amp Music Converter.

CD burner – slang for CD recorder.

CDD – Compatibilty Definition Document. A document provided by Google to enumerate the software and hardware requirement for professional audio on compatible Android devices.

CD-DA – Compact Disc Digital Audio. The standard format for audio compact discs as specified in the Red Book. Sometimes written as CDDA. See also Blue Book and Yellow Book.

CDDB – Compact Disc Data Base. An online database used to look up audio compact discs information. A CDDB-enabled player or CD ripper program calculates a nearly unique disc ID and then queries the database for a match. If a match is found, it displays the title of the CD, artist name, track list, and other information. CDDB is a licensed trademark of Gracenote, Inc. See also freedb.

CD duplication – see duplication.

CD duplicator – see duplicator.

CD-Extra – see Blue Book and Enchanced CD. Sometimes shown as CD+Extra.

CD+G – an audio compact disc format that in addition to audio data also contains graphics data. A CD+G disc can be played on a regular audio CD player, but when played on a CD+G-compatible player, it can output a graphics signal that can be sent to a television set or a computer monitor. Although originally designed to support video games, CD+G has become the standard for karaoke systems, where the graphics are used to display song lyrics.

CD-i – CD-Interactive. See Green Book and Enchanced CD.

CD manufacturing – see replication.

CD mastering – see mastering or replication.

CD player – is an electronic device designed to play audio from compact discs.

CD-Plus – see Blue Book and Enchanced CD. Sometimes shown as CD+Plus.

CD publisher – see CD duplicator.

CD quality – an audio file with a resolution of 16 bits and a sample rate of 44.1 kHz. The term is often misused to describe a file that sounds similar to CD quality, but actually is something less.

CD-R – CD-Recordable. A blank compact disc that can be recorded on once only. It can be played back in most CD players.

CD recorder – a device used to record digital music or other data on a writable compact disc, such as a CD-Recordable (CD-R, write once) or CD-Rewritable (CD-RW, write repeatedly). During the recording process, the data is burned into the disc with a laser. Informally called a CD burner.

CD replication – see replication.

CD-ROM – Compact Disc-Read-Only Memory. An optical disc used to store and play back computer data rather than digital audio. The specifications for the CD-ROM are defined in the Yellow Book standard.

CD-RW – CD-Rewritable. A compact disc that can be recorded, erased, and re-recorded many times. It can be played back in most CD players.

CDS – Cinema Digital Sound.

CDSA – Content Delivery & Security Association. See Media & Entertainment Services Alliance.

CD subcode – see subcode.

CD text – an extension of the Red Book specification for compact discs that adds the ability to include up to 5,000 characters of text, such as song titles, artist names, and album titles, on a music CD. This information can be displayed when the disc is played on a text-enabled CD player, and does not interfere with the normal operation of the CD player as the text is stored in the table of contents (TOC) of the disc.

CDV – CD Video.

CD-V – see CD Video.

CD+V – see CD Video.

CD Video – a format introduced in 1987 combining the technologies of compact disc and laserdisc, on a disc the same size as standard 12-cm audio CD. It contained up to 20 minutes of audio that could be played on any standard audio CD player plus up to 5 minutes of analog video with CD-quality sound, that could be played back on newer laserdisc players capable of playing CD-V discs. Another version called Video Single Disc (VSD) was released that only had the analog video track. The CD Video format, which was targeted at teenagers who watched music videos on MTV, never really caught on because most teenagers were not familiar with laserdiscs and even fewer owned CDV compatible players. Also known as CDV, CD-V, or CD+V.

CEA – Consumer Electronics Association.

CEE – Commission for Conformity Testing of Electrical Equipment. See IECEE.

ceiling cloud – an absorption panel suspended from a ceiling, usually in a horizontal position.

Celemony Software GmbH – an audio software company headquartered in Munich, Germany, specializing in pitch correction. It is best known for Melodyne, a pitch correction program similar to Auto-Tune®.

cell – (1) A storage spot in a software program, such as a a virtual instrument or loop-based plug-in, that can hold a sample, an audio loop, or a phrase. (2) A single electric energy-producing element of a battery, that consists of an electrolyte and metal electrodes in which a chemical reaction between the electrolyte and the electrodes generates electrical current.

cello – a string instrument with four strings tuned a fifth apart and pitched one octave lower than the viola. It is played with a bow while placed vertically on the floor between the players's knees. It is sized between a violin and a double bass. Short for violoncello.

cellulose nitrate – a chemical compound made by treating cellulose with nitric and sulphuric acids, used for film in the early days of movie making. It was replaced by acetate film because cellulose nitrate deteriorated fairly quickly and sometimes explosively. Also called (somewhat incorrectly from a chemical standpoint) as nitrocellulose.

Celsius – (1) A temperature scale in which water freezes at 0° and boils at 100° under standard conditions. It is named after the Swedish astronomer Anders Celsius, who developed a similar temperature scale. It was previously called centigrade. (2) A unit of measurement (degree) using the Celsius temperature scale.

CEMA – Consumer Electronics Manufacturers Association, now known as Consumer Electronics Association.

CEMF – Counter Electromotive Force. See back electromotive force.

cent – a unit used to measure intervals, equal to one one‑hundedths of a semitone (half step). Therefore, one octave consists of 1200 cents. An interval can be calculated in cents from the frequency ratio using the formula: Interval (in cents) = 1200 × log2 (f2/f1), where f2 and f1 are the frequencies. Using log10, the formula becomes Interval (in cents) = 1200 × 3.322 × log10 (f2/f1). Because a cent is a ratio of frequencies, it is a dimensionless number. It comes from Latin word centum, which means “one hundred.”

Interval	Frequency Ratio	Cents	Augmented Diminished
Unison	1.000000:1	0	Diminished Second
Minor Second	1.059463:1	100	Augmented Unison
Major Second	1.122462:1	200	Diminished Third
Minor Third	1.189207:1	300	Dimished Second
Major Third	1.259921:1	400	Diminished Fourth
Perfect Fourth	1.334840:1	500	Augmented Third
Tritone	1.414214:1	600	Diminished Fifth Augmented Fourth
Perfect Fifth	1.498307:1	700	Diminished Sixth
Minor sixth	1.587401:1	800	Augmented Fifth
Major Sixth	1.681793:1	900	Dimished Seventh
Minor Seventh	1.781797:1	1000	Augmented Sixth
Major Seventh	1.887749 :1	1100	Diminished Octave
Octave	2.000000:1	1200	Augmented Seventh

center-fed – see center-terminated capsule.

center frequency – the middle frequency between the upper and lower cutoff frequencies of a bandpass filter or a bandstop filter. It is usually defined as either the arithmetic mean or the geometric mean of the lower and upper cutoff frequencies. (A geometric mean is a type of average defined as the nth root of the product of n numbers.) See also Q. Also called a mid-band frequency or middle frequency.

center-terminated capsule – a condenser microphone capsule in which the electrical lead is attached to a post in the center of the diaphragm backplate, as opposed to a edge-terminated capsule. Examples of microphones with center-terminated capsules are the Neumann U 87 and the RØDE NT2. Also called center-fed.

centi- (c) – the SI prefix for a factor of one hundredth (10^‑2).

centigrade – see Celsius.

centimeter (cm) – a unit of measure in the CGS system equal to one hundredth of a meter, or approximately 0.3937 inch. British spelling centimetre.

central processing unit (CPU) – the main microchip on a computer motherboard that contains the circuitry necessary to control and carry out the processes of the computer.

ceramic – a material with a wide range of compositions, containing metals, nonmetals, and metalloids, a wide range of crystallinity from highly crystalline to semi-crystalline to amorphous, and a range of chemical bondings. Generally, ceramics have high melting points, high hardness, poor conductivity, high chemical resistance, and low ductility, but there are exceptions to each of these characteristics. In the audio world, ceramics are used in pickups, phonograph cartridges, loudspeaker magnets, and capacitors.

ceramic capacitor – a capacitor consisting of two or more layers alternating between ceramic material (the insulators) and metal layers (acting as the plates). See also electrolytic capacitor and film capacitor.

ceramic cartridge – see phonograph cartridge.

ceramic magnet – see ferrite.

ceramic microphone – see crystal microphone.

C filter – see C-weighting.

C. F. Martin & Company – a manufacturer of guitars headquartered in Nazareth, PA. It was founded in 1833 by Christian Frederick Martin, a German-born American luthier. Martin has also produced mandolins, electric guitars, and electric basses, but does not currently manufacture these.

C-format – (1) See UHJ. (2) See type C videotape.

CGGB – Composers Guild of Great Britain. See British Academy of Songwriters, Composers, and Authors.

CGS – Centimeter-Gram-Second, a version of the metric system that is no longer the preferred method of measurement, having been replaced by the SI system. See also MKS.

chain drive – a mechanism on a kick drum that uses a metal chain to connect the foot pedal with the beater, as opposed to a belt drive.

chair farts – slang for noise made by creaking chairs during a recording session.

chamber orchestra – see orchestra.

chamber reverb – a reverberation effect that simulates a reverb similar to hall reverb that provides a lush, ambient sound, but with extra clarity. This avoids the mudiness often found with hall reverb. Chamber reverbs can be used with many types of instruments including vocals, strings, and acoustic guitar, and drums.

Chandler Limited – an pro audio company headquartered in Shell Rock, IA. It was founded in 1999 by Wade Goeke in North Hollywood, CA. It produces modern day recreations of classic signal processors. It is the only authorized company in the world authorized to reproduce vintage EMI recording gear—the equipment used at Abbey Road Studios in the 1960s and 1970s.

channel – (1) A path in a device through which data or an audio signal can be routed. Also called an audio channel. Although channel is sometimes used incorrectly to mean track, technically they are not the same thing. For example, a 12-channel mixer can send audio to twelve tracks of a multitrack recorder. However, a stereo track can contain two channels. See definition #2. (2) One side of a stereo signal, such as the left channel or the right channel. (3) A channel strip. (4) In a MIDI system, one of 16 possible data paths over which MIDI data may be sent, allowing up to 16 different MIDI instruments or parts may be addressed with a single cable. (5) In television broadcasting, a set of frequencies, usually one for audio and another for video, that is assigned a number, with different frequencies used for analog and digital transmissions. A government agency (the FCC in the US) assigns these to various television stations, and more than one station can occupy the same channel, but at some distance from one another so as to not cause interference. The bandwidths of TV channels varies from country to country as well as the channel numbering system. (6) A radio frequency designated for use with certain devices, such as wireless microphones or Wi-Fi systems. (7) A complete, self-sufficient recording setup. For example, a production channel includes a recorder, mixer, microphones, monitors, and headphones.

channel assign – see assign.

channel climb – see pre-chorus.

channel count – (1) The number of audio channels present in a particular device, such as a console, mixer, or audio interface. (2) The number of channels of audio, MIDI, or virtual instruments being used for a specific project. See also track count.

channel coupling – a method used to reduce bit rate when encoding digital audio by reducing interchannel redundancy in order to code the stereo information more efficiently. For MP3 the channel coupling is called joint stereo. For other codecs, coupling methods include (a) Simple stereo (SS) (also called L/R stereo, dual stereo, or dual mono) - coding in which each channel is treated as completely separate signals, with no reduction in redundancy. (b) Mid-side stereo (MS) - coding that creates a mid-side matrix using the sum and difference of the left and right stereo signals. (c) Intensity stereo (IS) - coding that replaces the left and the right signal with a single stream that includes the signal plus directional information. (d) Lossless coupling - simple stereo with with additional space-saving enhancements. (e) Point stereo - coding in which the stereo information is the difference in the spectral floors for the left and right channels. (f) Phase stereo - coding in which stereo phase (essentially the stereo differences between the two channels, not the phase of a sine wave) is stored at a lower resolution. Also called joint coupling.

channel jumping – sending the same signal from a guitar to two different channels of a two-channel guitar amplifier. Depending of the amplifier model, this can be done by using separate inputs or by using a jumper cable to go from one input to the other. Channel jumping allows for choosing different preamps (if available) or setting up each channel with different effects, such as equalization, reverberation, and tremolo. The two channels can be used independently or blended to achieve the desired effect.

channel separation – the amount of difference in level measured in decibels (dB) between the two channels of a stereo signal, when one channel is fed a signal and the other is not. Lack of channel separation leads to crosstalk.

channel strip – the vertical strip of controls for an audio channel, such as on the front panel of a mixer, console, or digital audio workstation. Sometimes called an input module, a holdover from the days when consoles were built in a modular format.

charge – (1) An electric charge. (2) To store electrical energy in a device such as a battery.

charger – a transformer used to charge the battery in an electronic device. See also power adapter.

chart – (1) A musical score. (2) An informal musical score, typically used by jazz musicians, containing only minimal music notation. (3) To create such a chart. (4) A listing by popularity of records, songs, and albums of a particular type or genre, such as the Billboard Top 100. (5) To appear on a listing of popular records, songs, and albums.

chase – (1) To automatically synchronize the speed of one device (the slave) with that of another (the master). The slave is said to be chasing the master. (2) A MIDI process in which prior to playback the device looks back to earlier MIDI events to see if there were any program or channel change messages that would affect the playback from the current point.

chassis – the structural framework, usually made of metal, on which a piece of audio, radio, or computer equipment is mounted.

chassis ground – a ground connecting the chassis of a device to a common grounding location, such as a rack rail, on a multi-component electronic system. This connection provides a zero potential voltage reference and a point for dissipation of interference, transient voltages, and static charges.

chatter – audio that goes in and out due to a noise gate being set too close to the threshold level causing the gate to open and close rapidly. The problem can be corrected by adjusting the threshold level.

Chebyshev filter – an analog filter or digital filter that has a steeper roll-off slope but more ripple than a Butterworth filter. A Chebyshev filter very closely approaches the characteristics of an idealized filter having a flat stopband but with ripples in the passband (Chebyshev Type I) or a flat passband and ripples in the stopband (Chebyshev Type II), but it does not have ripples in both the passband and the stopband. This type of filter is named after Pafnuty Chebyshev because it was designed using the Chebyshev function. Sometimes spelled Tchebyschev or Tchebyscheff.

cheap speaker check – see mix speaker check.

check monitors – see mix speaker check.

checksum – a number derived using a mathematical formula on data, that can later be checked to detect errors in the data, a form of error detection.

Cher effect – a slang term for the effect created by using pitch correction in an extreme manner to produce an artificial sounding voice. The effect was first used and made popular by the Cher in her 1998 song “Believe.” It has since become prevalent in many rap and hip hop songs. Also called the T-Pain effect.

chesty – (1) Sounding like a vocalist with an oversized chest. (2) A descriptive term for a sound with a bump in low frequency response, around 125 Hz to 250 Hz.

chiff – (1) The burst of white noise at the beginning of a note played by a pipe organ or whistle, analogous to the “ch” sound in the word chiff. (2) The hiss of white noise heard during a note played by an organ or whistle.

chicken picking – a guitar picking technique that resembles a chicken clucking. The picking hand finger is used to mute a string while it is plucked with a pick, creating a percussive sound. The cluck is created when the picking hand finger plucks the string and lets it twang back against the fretboard.

china cymbal – a a type of cymbal that produces a dark, crisp, trashy, and explosive tone somewhat resembling that of a Chinese gong.

chip – (1) Slang for microchip. (2) Another name for a swarf.

chirping – a high pitched sound similar to birds chirping caused by the over use of a single-ended noise reduction system.

chipset – a collection of integrated circuits that form the set needed to perform certain functions in a computer, smart phone, and other electronic devices.

choir – (1) A group of singers, especially one that performs in church services or in public. (2) A group of instruments of the same type, such as a brass choir.

choke – an inductor used to block higher-frequency alternating current (ac) in an electrical circuit and passing through direct current (dc) or lower-frequency ac. A choke usually consists of a coil of insulated wire wound on a magnetic iron core that looks much like a transformer, but has only two leads. They are sometimes used in the power supplies of guitar amplfiers to smooth out the rectified dc. The name is due to the fact that it “chokes” out high frequencies. If it is used in electronic filters or tuned circuits, it is simply called an inductor.

choking – see damping or choke.

chord – a combination of two or more (some say three or more) musical notes with specific intervals that are played together. Chords form the basis of harmony. See also dyad.

chord change – see chord progression.

chord chart – (1) An informal musical score, typically used by jazz musicians, containing only minimal music notation. Called a chart for short. (2) A diagram that shows a chord progression. It can be as simple as a series of chord symbols above a traditional musical staff. In the Nashville number system numbers are used for chord names and the key is left unspecified to facilitates on-the-spot key changes to songs. (3) A diagram indicating the fingering on the frets of a stringed instrument. Also called a tablature.

chordophone – a classifications for musical instruments that produces sounds through the vibration of string according to the Hornbostel-Sachs system of musical instrument classification. Examples include piano, harp, violin, or guitar. The other four classifications are electrophone, idiophone, membranophone, and aerophone.

chord progression – a series of musical chords, or chord changes, that establish a tonality in a given key, root, or tonic chord, and that is based upon a succession of relationships. Also called a chord change or harmonic progression.

chord shape – the position of the fingers when playing a particular chord on a string instrument. By moving the chord shape up the fingerboard of the instrument, addtional chords can be played. See movable chord

chord tone – - the notes that make up a given chord. See nonchord tone.

chorus – (1) The part of a song that is repeated and has the identical or nearly identical music and lyrics. Also called a refrain. (2) A singing group composed of many singers.

chorused effect – see chorusing.

chorusing – an effect that simulates a vocal chorus by (a) adding several delays, usually in the 15 to 30 msec range, with a small amount of feedback or by (b) detuning the sound very slightly and adding it back into the original with a slight delay. Analog chorus creates this effect using analog circuits. Digital chorus creates the effect using digital DSP algorithms. Compare with flanging and phasing. Also called chorused effect.

chroma – the signal in a video system that conveys the color information of the picture, separately from the luma signal (Y). Also called chrominance and abbreviated C. See also YUV.

chromatic alteration – the raising or lowering of a musical note by a semitone (half step).

chromatic accordion – see accordion.

chromatic chord – a chord that includes at least one note that does not not belong to the diatonic scale of the key being used. Any chord that is not chromatic is a diatonic chord. Examples include the Neapolitan sixth chord (♭II, for example in C Major, F-A♭-D♭), which resolves to the V (see Roman numeral analysis, the sharpened subdominant with diminished seventh chord (♯iv, for example, F♯-A-C-E♭), which resolves to the V, and the augmented sixth chord (♭VI, for example, A♭-C- F♯), which resolves to the V. Also called chromatic harmony.

chromatic diesis – see syntonic comma.

chromatic harmony – see chromatic chord.

chromatic scale – a musical scale consisting of all twelve semitones (half steps) in an octave. In western music, all other scales are subsets of the chromatic scale.

chromatic tuner – an electronic tuner that can detect and display tuning for all 12 notes on the chromatic scale.

chrome equivalent – see cobalt-modified tape.

chrome tape – see chromium dioxide.

chrominance – see chroma.

chromium dioxide – a synthetic magnetic material once widely used in formulations for magnetic recording tape. Chromium dioxide crystals are very uniform and can be evenly and densely dispersed in a magnetic coating, that has high coercivity and remanence. This made chromium dioxide ideal for use in high-performance recording tape for the audio cassette, with had previously had poor high-frequency response and tape hiss problems. However, chrome tapes required newly designed cassette recorders with about 50% higher bias current and a new equalization setting (70 μs), but resulted in a 5 to 6 dB improvement in signal-to-noise ratio over ferric-oxide audio tapes. The same bias and EQ settings were later used with cobalt-modified tapes, which were designated as “chrome-equivalent” formulations. Chromium dioxide tape is also called chrome tape and designated as Type II.

chucking – see fret hand muting.

CIEM – Custom In-Ear Monitors. In-ear monitors (IEM) that are custom-made to fit an individual's ears. An audiologist makes an ear impression that is used to create the monitors.

cigar mic – see pencil mic.

Cinch jack – see phono jack.

Cinch plug – see phono plug.

cinema – (1) A movie theater. (2) The production of motion pictures. (3) The motion picture industry.

Cinema Audio Society (CAS) – an organization formed in 1964 of sound professionals in the motion picture and television industries. Sound professionals include recordists, technicians, audio mixers, Foley artsts, sound editors, and personnel involved in music scoring, post production, and ADR. The CAS holds periodic educational meetings on topics of interest to those in the industry. Annually the CAS presents the CAS Awards for outstanding achievement in sound mixing for feature films and television.

Cinema Digital Sound (CDS) – a multi-channel (5.1) surround sound format used for movies in the early 1990s, developed by Optical Radiation Corporation, a division of Eastman Kodak. Within two years, CDS had been superseded by Digital Theatre System (DTS) and Dolby Digital.

CineMag, Inc. – a company founded in 1979 in North Hollywood, CA, by Tom Reichenbach, that manufactures high quality audio transformers and inductors. Before he started CineMag, Tom worked for his father Ed Reichenbach who had formed Reichenbach Engineering in the 1950s. CineMag was originally located at Reichenbach Engineering, but when it outgrew the facility, it moved the manufacturing facility to Canoga Park, CA.

CISAC – Confédération Internationale des Sociétés d'Auteurs et Compositeurs (International Confederation of Societies of Authors and Composers). A worldwide network of authors' societies consisting of 231 collective management organizations in 121 countries protecting the interests of creators and rights holders.

CIRC – Cross-Interleaved Reed-Solomon Code. An error detection and correction method used in compact disc players.

circle of fifths – a diagram used to aid musicians and music teachers that shows the relationships of keys, key signatures, major scales, and minor scales. It consist of a circle around which all 12 major scales (usually on the outside) and 12 minor scales (usually on the inside) are arranged such that any pair of adjacent scales represents a perfect fifth. See the full diagram of the circle of fifths.

circle progression – a chord progression that progresses through all seven diatonic chords of a diatonic scale descending by fifths and returns to the tonic at the end. In other words, it progresses around the circle of fifths. It could also move around the circle in the opposite direction by fourths. For example, a circle progression in Roman numeral notation would be: I-IV-viii°-iii-vi-ii-V-I. For the key of C major, the progression is C-G-Dm-Am-Em-B°-F-C. Shorter circle progressions are possible and can be derived by selecting portion of the full circle of chords.

circuit – (1) A path through which an electric current passes. Called an electrical circuit or electric circuit. (2) An assembly of components, such as transistors, resistors, and capacitors, designed to perform a particular function. Called an electronic circuit. (3) An integrated circuit that performs a function as in definition #2 above. See also electrical network. (4) All paths and components needed to accomplish one function in a device.

circuit board – (1) A thin sheet of fiberglass or other material onto which electronic components, such as transistors, resistors, capacitors and microchips, are installed to create an electronic circuit. Circuit boards are used in electronic devices such as amplifiers, receivers, and computers. Called a board for short. (2) Short for printed circuit board.

circuit breaker – a safety device consisting of an automatic switch that breaks the electric circuit when the rated level of current is exceeded. See also fuse.

circuit ground – the reference point in a circuit at which voltages are measured or a common return path for electric current. The circuit ground may or may not be connected to earth ground.

circuit node – any point in a circuit where two or more elements meet, with each node having a different voltage.

circuit protective conductor (CPC) – British term for a mechanism in which all exposed conductive parts of a system are joined together and connected to the main ground (earth) terminal. Called an equipment grounding conductor in the US.

circuitry – a circuit or a system of circuits that perform a particular function in an electronic device.

circular frequency – see angular frequency.

circumaural – literally means “around the ears” and refers to headphones with large cushions that surround the ears and excludes external noise. See also supraaural and intraaural.

C-Lab – the German software company that was a forerunner to Emagic, which was purchased by Apple in 2002.

clarinet – a musical instrument in the woodwind family having a straight cylindrical-bored tube with a slightly flared bell and a single-reed mouthpiece, played by means of finger holes and keys. There are many types of clarinets and most of them are now rare or obsolete. Clarinets in use today include the B♭ clarinet or soprano clarinet, the one most people think of for the term clarinet. Others include the alto clarinet and the bass clarinet.

class A amplifier – an amplifier in which the output voltage is always positive. Generally class A amplifiers use a single transistor or vacuum tube, which always have current flowing through it, even with no signal present, because a tube or transistor can handle current in only one direction. Class A amps use more current, generate more heat than other classes, and have as little as 15% efficieny, but they have the highest linearity. They have a low level of distortion and tend to be the best sounding of the conventional amplifier classes.

class AB amplifier – an amplifier which uses a combination of class A and class B designs to achieve efficiency than class A but with lower distortion than class B. By combining two vacuum tubes or transistors operating on opposite sides of the zero crossing line, the crossover distortion found in class B amplifiers is essentially eliminated, without the inefficiency of the class A amplifier. The two tubes or transistors have a very small bias voltage so that both are on for more than one half cycle, but much less than one full cycle of the input signal. The class AB amplifier is a good compromise between class A and class B, with good linearity and having an efficiency of about 50% to 60%.

class B amplifier – an amplifier in which current flows only for half a cycle. Alternatively, two transistors or vacuum tubes can be used in a push-pull manner, each operating for half a cycle. Although this class is more efficient (about 50%) and has fewer heating problems than class A, it is typically used only in low-end products, because it has crossover distortion, distortion at the zero-crossing point, resulting in a lack of linearity.

class C amplifier – an amplifier that operate for less than half of one wave cycle. Class C amplifiers are the most efficient, but they are not used for audio applications because they have excessive distortion.

class D amplifier – an amplifier that works like digital. It puts out a signal equivalent to an analog output, but it uses pulse width modulation (PWM) or pulse density modulation (PDM). Because pulse modulation output signals are either on or off, class D amplifiers produce far less heat than analog amplifiers and have efficiencies greater than 90%. They are widely used in a variety of applications from high-end audio to amplifying cellphone speakers. Although it is sometimes claimed that class D stands for “digital,” that is not the case. D was simply the next letter after Class C. Sometimes it is called incorrectly a digital amplifier, but technically it is not digital because the output is not digital data, but a modulated audio signal that acts like analog, which is sometimes called “synthesized analog.”

class E and class F amplifiers – amplifiers used in radio frequency application, but not in audio work.

class G and class H amplifiers – Class G amplifiers use enhanced designs of class AB amplifiers to improves efficiency by switching to different fixed voltages as the signal approaches those voltages. A further enhancement of class G is class H, in which the power supply voltage is modulated and always slightly higher than the input signal.

classical guitar – (1) A type of acoustic guitar used to play classical music. It is a wooden guitar having a classical shape resembling early guitars from France and Italy, with six classical guitar strings. Unlike electric guitars and acoustic guitars used in popular music, the classical guitar strings are usually made of a polymer (usually nylon) with a fine silver wire wrap on the bass strings. Originally, the strings were made of catgut. Also called a Spanish guitar. (2) A style of guitar playing in which the strings are plucked with the fingernails or sometimes with the fingertips. (3) The style of music played on a classical guitar.

classic electret condenser microphone – see electret condenser microphone.

class T amplifier – an amplifier that uses a class D audio amplifier switched at very high frequencies (on the order of 50 MHz). Class T is a registered trademark of Tripath, which was acquired by Cirrus Logic in 2007. Similar designs have now been developed by other manufacturers.

clean – a sound free of distortion, interference, leakage, and noise. The opposite of dirty.

clean room – an space free from dust and other contaminants, used in such applications as the manufacture of electronic components.

clear – (1) Easy to hear or differentiate. (2) A descriptive term for a sound with sufficient high frequencies. The opposite of muddy. (3) Transparent.

clef – one of several symbols placed at the beginning of a music staff indicating the pitch of the music. Although there are seven clefs (treble clef (G clef), bass clef (F clef), and five C clefs), only three are commonly used today. The table below shows what clef various instruments typically use. The five C clefs are soprano clef (with C on the first line [bottom line]), mezzo-soprano clef (C on the second line), alto clef (C on the middle line), tenor clef (C on the third line), and baritone clef (C on the fifth line [top]).

Treble Clef (Concert Pitch)	Bass Clef (Concert Pitch)	Alto Clef (Concert Pitch)	Treble Clef (Transposed)
Piano	Cello	Viola	Piccolo
Organ	Trombone	Viol	B♭ Clarinet
Harpsichord	Tuba	Gamba	B♭ Trumpet
Flute	Bassoon	Alto Trombone	B♭ Cornet
Violin	Euphonium	Mandoloa	French Horn
Oboe	Baritone Horn		Saxophone
Guitar	Double Bass
Mandolin

CLF – Common Loudspeaker Format. A specification to be used by loudspeaker manufacturers, designers, and others to present loudspeaker data in a uniform format.

click and pop reduction – a feature in some audio equipment that eliminates clicks and pops when powering up or down equipment or when connecting a new source.

clicks and pops – unwanted transient noise in an audio signal caused by a variety of sources, such as dirt and dust in the grooves of a phonograph record, the powering up or down of audio equipment, or when connecting a new source. See also impulse noise.

click track – a series of clicks or other sounds played at precise intervals at a specified tempo and sent to musicians via headphones to maintain that tempo during a recording session. Beside helping musicians maintain proper timing, it also aids the engineer when editing later on. Called a metronome in some DAWs.

client – computer hardware or software that accesses a service from a server. It is considered to be part of a client-server model.

client ref – slang for client reference, a recording made for the client to approve before mass production begins. When vinyl was the rule, the client ref was usually delivered as an acetate record. Today it typically comes as a CD-R.

client-server – see client and server.

clip – (1) To drive an analog signal beyond its limits causing distortion. (2) To drive a digital signal to greater than 0 dBFS, resulting in distortion. (3) A portion or all of an audio file usually designated for editing purposes in a DAW. Other DAWs may be refer to this as a region, event, segment, zone, or sound bite. (4) A snippet of audio used in looping. Sometimes called a loop, audio loop, or sample loop. (5) A segment of a media file, such as an audio clip or video clip.

clip automation – a feature of some DAWs that allows for automation to work on an audio or MIDI clip. Clip automation is applied first followed by track automation,if any.

clip envelope – the name used in Ableton Live for the graphical representation of the changes in various parameters such as automation, modulation, and mixer data for a given clip. See also automation envelope.

clip gain – an adjustment available in many DAWs that allows the user to adjust the level of a region (clip) of recorded audio. It can be used to adjust the level of a entire clip or sometimes used to adjust varying levels by chopping a recording into smaller clips that can be adjusted individually.

clipping – (1) The condition that occurs when an analog signal exceeds the level that a particular device can accommodate. Hard clipping is extreme clipping that produces easily observed flat-toped waveforms when viewed on an oscilloscope. Soft clipping is a more moderate form of clipping with waveforms that are more rounded on an oscilloscope. (2) The condition that occurs when a digital signal is greater than 0 dBFS, causing the tops of the peaks to be “clipped” off, resulting in distortion. As a general rule digital clipping should be absolutely avoided because of the harsh and dissonant sound it produces.

clipping level – the maximum output signal (measured in dBV or dBu) that a microphone can produce before the signal becomes distorted.

clock – a timer that send out pulses or other signals used by various devices to maintain synchronization among the devices. The clock consists of a crystal or other device that oscillates at a very accurate high frequency. For example, the crystal may oscillate at 11.2896 MHz, but when divided by 256 it creates the desired frequency of 44.1 kHz. Although the clock produces a very precise frequency, there are slight differences from one clock to another. For that reason, a master clock should be used to provide the clock signal when using several digital devices at the same time. See also timebase.

clock jitter – see digital jitter.

clock rate – see operating frequency.

clock reference – see synchronization signal.

clock resolution – the precision (measured in PPQN) with which a sequencer can encode time-based information. Also called timing resolution.

clock signal – see synchronization signal.

clone – (1) A microphone that has been designed and manufactured to recreate the performance, and sometimes also the look and feel, of a vintage microphone. (2) To design such a microphone.

clonewheel organ – slang for an electronic musical instrument that emulates the sound of the electromechanical organs formerly manufactured by Hammond that created sounds using tonewheels. Clonewheel is a play on the term tonewheel.

closed-air headphones – see closed-back headphones.

closed-back headphones – a type of circumaural headphones that forms a seal around the ear to provide more isolation between the headphone signal and outside sounds than open-back headphones. Also called closed headphones or closed-air headphones.

closed headphones – see closed-back headphones.

closed circuit – (1) An electric circuit that provides a complete path for current. (2) A television system that has no broadcast facilities with the signal being distributed usually by cable to a limited number of receivers.

closed-loop drive – see dual capstan.

close harmony – harmony in which the notes of a chord are kept very close together, typically within one octave.

close field – see near field.

close microphone – a microphone used for close miking.

close miking – placing a microphone close to the sound source (usually two feet or less) to pick up the desired sound and decrease the pick up of extraneous sounds or leakage. Close miking also minimizes the sound of the room. Also called close pickup. When close miking is used with distant miking to add presence or to improve clarity, blending, and tonal balance, it is called spot miking or accent miking. See also ambient miking. Sometimes spelled close micing or close mic'ing.

close pickup – see close miking.

cloth track – the audio track that contains the Foley sound effects. This term is used on west coast. On the east coast, it is called a rustle track. These names are derived from the rustling of clothing.

cloud – servers that are maintained and controlled by any one of a number of a cloud computing providers that are used to store data and information remotely. Stored data on “the cloud” is accessed using an internet connection.

cloud audio collaboration – see remote collaboration.

cloud-based session sharing – see remote collaboration.

cloud computing – using a network of remote servers (“the cloud”) hosted on the internet to store, manage, and process data, rather than using storage on a personal computer or local server. Cloud computing also allows recording studios to collaborate remotely.

club music – see electronic dance music.

cluster – see line array

CLV – Constant Linear Velocity.

CM microphone – see Controlled Magnetic microphone.

CMRR – Common-Mode Rejection Ratio.

CMYK – Cyan-Magenta-Yellow-Key. A color model using a mixture of four process colors: cyan, magenta, yellow, and black. CMYK is the standard color model used in offset printing and computer printers. The key color is black, but during earlier times, other colors have been used as the key, such as been brown, blue, or black, whatever was cheapest at the time. It is sometimes called four-color printing.

coax – short for coaxial cable.

coaxial – (1) Having or being mounted on a common axis, such as a coaxial speaker. (2) Using or being connected to a coaxial cable.

coaxial cable – a two-conductor cable consisting of one conductor surrounded by second conductor that acts as a shield. Called coax for short.

coaxial loudspeaker – a loudspeaker system in which the high-frequency driver (tweeter), the mid-range driver (in a 3-way speaker system), and the low-frequency driver (woofer) are mounted on the same axis. With this configuration the sound of all drivers seem to be coming from the same point, which produces better dispersion and phase coherence. Also called single-source loudspeaker or dual-concentric loudspeakers.

coaxial monitor – a studio monitor using a coaxial loudspeaker design.

coaxial speaker – see coaxial loudspeaker.

cobalt-modified tape – a magnetic recording tape in which the ferric oxide formulation is doped with a small amount of cobalt, which imparts improved coercivity and remanence. Because this modification uses the same bias signal and equalization setting (70 μs) as chromium dioxide tape, it is called a “chrome-equivalent” formulation and is designated as Type II.

CobraNet – a method for sending uncompressed, multichannel, and low-latency digital audio using audio over Ethernet (AoE) protocols.

cockpit problem – slang for operator error.

cockpit trouble – slang for operator error.

coda – the section of music that brings a passage to a conclusion.

code – (1) Computer program instructions. (2) To write a computer program. (3) To encode a file into a different format or to compress the file into a smaller size.

code 18 – slang for operator error.

codec – a process of coding and then decoding an audio signal in order to compress it. Examples include MP3, WMA, and AAC. The term is a condensation of code-decode or compress-decompress.

coercivity (Hc) – the magnetic field strength (measured in oersteds) required to take a fully saturated recording tape to complete erasure.

coil – insulated wires wrapped around the core of a transformer. A primary coil is the coil in which current is driven by an outside alternating-current power source. A secondary coil is the coil whose voltage is induced by the varying magnetic field produced by the primary coil. The varying magnetic field induces a voltage in the secondary coil, which transfers electrical energy without making electrical contact. Although most transformers have one secondary coil, some designs have two or more secondary coils. Also called a winding, with the primary coil and secondary coil are called primary winding and secondary winding, repectively, or simply primary and secondary.

coincident pair – a group of stereo microphone techniques in which the heads of two microphones (or one stereo microphone) are placed very close together so that the sound path reaching each of them is essentially the same for all sound sources. Techniques in this group include: Blumlein array, mid-side, and X-Y pair. See also near-coincident pair (A-B, DIN, EBS, Faulkner array, NOS, ORTF, and RAI) and spaced pair (A-B, Decca tree, space cardioid, and spaced omnis. See also table comparing various stereo microphone techniques.

cold – (1) A descriptive term for a sound that lacks warmth. It is sometimes used as a derogatory term to describe digital recordings. (2) A descriptive term for a sound with too much high end, especially above 10 kHz.

Coles Electroacoustics Ltd. – a company founded in 1964 and headquartered in Hoddesdon, Hertfordshire, UK, that manufactures microphones and audio equipment. The name comes from the first names of the founders, Colin and Les. They began by building amplifiers in their garage, but eventually moved into larger facilities. In the mid 1970s they began producing microphones for Standard Telephones and Cables, Ltd. (STC), but when STC decided to stop selling microphones, they acquired the rights and manufacturing equipment, and continued to produce the microphones under their own name.

Coles 4038 – a ribbon microphone produced by Coles Electroacoustics. It was designed by the BBCin 1953 and assigned the model number BBC PGS/1. It was a more robust microphone than the RCA 44-A. The 4038 was produced by Standard Telephones and Cables as the STC 4038. Coles acquired the right and began manufacturing the mic under their own name in the mid 1970s. The microphone had a better frequency response than the 44-A and has been described as having a “British sound.” It has been described as having the look of a waffle iron. It is used in both recording studios and radio broadcasting. The technical specifications of the 4038 have remained unchanged since its introduction in 1953.

coloration – a distortion of the frequency response of a sound signal, sometime pleasing (warm coloration) and sometimes not. British spelling is colouration.

colored – (1) Sounds with timbres that are not real or true to life. (2) A frequency response with distortion, i.e. having peaks or dips. See also coloration.

color gamut – the range of colors that a particular device, such as a computer monitor, television display, or printer, is capable of displaying.

colored noise – see noise colors.

color model – see color space.

color space – a system for the encoding color into a numerical format. For example, the color space for scanners, cameras, and displays is RGB, for color printing is CMYK, and for television and video is YUV. Also known as a color model.

color space conversion – the process of changing from one type of color-encoded signal (color space) into another, such as converting from RGB to YUV or from the computer display color (RGB) to the printer color (CMYK). Because color spaces may have different color ranges, conversion sometimes results in a loss of color.

Columbia Graphophone Company – a UK record company founded in 1922 when the US company Columbia Records (then known as Columbia Phonograph) sold its UK subsidiary. After Columbia Phonograph went into receivership in 1923, Columbia Graphophone bought its former parent in 1925. It acquired Odeon Records and Parlophone Records in 1926. In 1931, the Gramophone Company and the Columbia Graphophone Company merged to form Electric and Musical Industries (EMI). US anti-trust laws required EMI to sell its US subsiary Columbia Records. EMI continued to issue recordings under the Columbia label in the UK until the early 1970s. It also issued records on the Columbia label in many other countries (except in the US, Canada, Mexico, Spain and Japan) until 1990 when it sold its remaining interest in the Columbia trademark to Sony Music Entertainment, who owned Columbia Records in the US and Canada.

Columbia Records – a record label founded in 1888, the oldest label still in existence. Its name came from the District of Columbia, where it was originally headquartered. It evolved from the American Graphophone Company, a successor to the Volta Graphophone Company. In 1923, Columbia went into receivership and the company was bought by its UK subsidiary, the Columbia Graphophone Company in 1925. In 1931, the Gramophone Company and the Columbia Graphophone Company merged to form Electric and Musical Industries (EMI). Because of US anti-trust laws EMI was required to sell its US subsiary, which was purchased by the Grigsby-Grunow Company. In 1934, Grigsby-Grunow fell on hard times and sold Columbia to the American Record Corporation (ARC). In 1938, ARC was purchased by William S. Paley of the Columbia Broadcasting System (CBS), which had been co-founded by Columbia Records itself in 1927. CBS renamed the company Columbia Recording Corporation. It used EMI to distribute its records outside the US until 1951, when it began using Philips Records for distribution. In 1961, CBS ended its arrangement with Philips and began distribution through its own organization, CBS Records International. (Records could not be released under the Columbia name because EMI operated a record label by that name outside North America as part of the merger creating EMI.) The CBS Records Group, which included Columbia Records, was acquired by Sony in 1988, becoming the Sony Music Entertainment in 1991. The CBS Records label was renamed Columbia Records worldwide except Spain and Japan. Sony had also acquired Columbia Pictures in 1989. Colubia became one of the three flagship labels of Sony Music Entertainment, with the other two being Epic Records and RCA Records.

comb filter – a filter whose amplitude response exhibits an equally-spaced series of peaks and notches when graphed linearly versus frequency, which resembles the teeth of a comb. This effect occurs when a direct signal mixes with a signal of the same strength that is delayed by a small amount of time. Note: Because the arrival time differs for each ear, the comb filtering effect is different at each ear.

combining amplifier – an amplifier in which two or more audio signals are mixed together to feed an audio bus, signal processor, or a single track of a tape machine. Devices that perform this function can be either an active combining amplifier (ACA) or a passive combining network. Also called a summing amplifier.

combining network – a passive network that mixes two or more signals to feed an audio bus, signal processor, or a single track of a tape machine. If the network has gain, then it is an active combining network or active combining amplifier.

combo – (1) Short for combination. (2) A combo amp. (3) A musical group, band, or ensemble typically those of a pop or jazz genre.

combo amp – an instrument amplifier, such as a guitar amplifier, that includes the amplifier (head unit) and speakers in one cabinet, as opposed to separate head unit and speaker cabinet.

combo connector – a connector that combines a 3-pin female XLR receptacle and a ¼-inch phone jack developed by Neutrik. It accepts balanced inputs, line inputs, or instrument inputs in one jack. The phone jack can be TS or TRS.

comma – a very small interval in music, the difference that results from the same note being defined in two different ways. For example, using the same tuning system, two enharmonically equivalent notes (such as G♮ and A♭) may have slightly different frequencies, with the interval between them being a comma. The difference between the same note being tuned using two different tuning systems is called a syntonic comma.

comma of Didymus – see syntonic comma.

commentary sound – see non-diegetic sound.

Commercial Advertisement Loudness Mitigation (CALM) Act – a US law that went into effect in 2012 requiring commercial advertisements to be the same loudness as the program material in television transmissions.

commercial music – (1) Music within the mainstream music industry released to sell or stream to the public. (2) Any music produced to make money, sometimes used derogatorily to indicate music made to appeal to the masses rather than created artistically.

commit – a function in Pro Tools 12.3 or higher in which plug-ins, virtual instruments, and other functions in a track or selected portion of a track are put into freeze mode and bounced to a new track to save processing power. Freeze, a function available in many other DAWs that became available in Pro Tools 12.4, is especially useful for sending a track to another user or collaborator. If the other user does not have the same plug-ins, then the track can be worked on with the effects in place. If the other user has the same effects, then the user can unfreeze the track and make adjustments as necessary. See also render.

common mode – a signal that is referenced to the circuit ground. This is the opposite of differential mode or normal mode.

common mode noise – electrical interference on the two signal lines of a balanced line caused by each line having a different potential relative to ground. It is called common because the noise is common to both lines.

common-mode rejection ratio (CMRR) – the measure of the amount of cancellation of common signals at the input of a balanced line. One line of a balanced cable has a positive signal and the other line has a negative signal (opposite polarity of the other line). In theory any signal common to both lines should be cancelled at the receiving end. CMRR is the tendency to reject such common signals of balanced lines and other similar devices. See also common mode noise.

common time – a time signature indicated with the symbol C, which stands for 4/4 time, signifying four quarter-note beats per measure. If the symbol has a vertical line through it, it indicates cut time. Also called imperfect time.

communication protocol – a system of rules use in telecommunications to allow two or more elements in a communications system to transmit information between them. A protocol provides the rules, syntax, semantics, and synchronization of communication and sometimes error recovery methods. Protocols may be implemented using hardware, software, or a combination of both.

comp – short for composite.

compact cassette – see cassette.

compact disc (CD) – a 4.7-in (120 mm) diameter optical disc that contains data or audio. Compact discs come in several varieties, including CD-DA (Compact Disc Digital Audio)—a commerically produced audio disc, CD-R (write-once recordable disc), CD-RW (recordable and rewritable disc), and CD-ROM (a read-only data disc). The Mini CD has a diameter ranging from 60 mm (2.4 in) to 80 mm (3.1 in). See also Blue Book, Red Book, Yellow Book, White Book, Green Book, and Orange Book.

compact disc subcode – see subcode.

compander – (1) a device that contains a section to first compresses a signal before recording or broadcast and a section section that expands the recorded or broadcast signal. (2) A device that provides both compression and expansion in the same device.

companding – the process of first compressing a signal before recording or broadcast and then expanding the recorded or broadcast signal. The word is a combination of compressing + expanding. Also called compansion.

compansion – see companding.

comping – the process of maling a composite, combining the best segments of several takes of a performance onto one usable track (the composite track). Short for compositing.

complementary – any pair of audio signal processing procedures that perform equal but opposite processes on an audio signal, one during recording/broadcast and the other during playback/reception. Noise reduction and pre- and de-emphasis are examples.

complementary station – see broadcast translator.

complex impedance – an impedance that includes both magnitude and phase. It is composed of a real part (a resistor) in series with a imaginary part (a coil or capacitor) and is measured in ohms. It is represent by the letter Z.

complex wave – a wave containing more than one frequency component. See also waveform.

compliance – the measure of the softness or “springiness” (the inverse of stiffness) of a phonograph cartridge, measured in micrometers per millinewton (μm/mN) or 10^‑6 centimeters per dyne (cm/dyne), both units often called cu for compliance units. Compliance is important because it must be matched with a tonearm of the correct mass. The compliance together with the effective mass of the tonearm and cartridge determine the fundamental resonance of the tonearm. For optimal results the resonant frequency should be maintained between 8 to 14 Hz, although some say it should be limited to 9 to 11 Hz. The formula for estimating the resonant frequency of a tonearm + cartridge is f_r = 1000/[6.28 × square root (M × C)], where M is the mass of the tonearm and cartridge in grams and C is the compliance of the cartridge.

compliance unit (cu) – μm/mN or 10^‑6 cm/dyne. See compliance.

component – (1) A part or element of a larger whole, such as a part of a machine or device. (2) An electronic component. (3) A part of a stereo system, such as a tuner, amplifier, or speaker.

component analog video (CAV) – see component video.

component video – a video signal that has been split into two or more component parts. It usually refers to component analog video (CAV), in which a video signal is transmitted as three separate signals in contrast to composite video where all the video information is combined into a single analog line-level signal. Neither component nor composite video carries any audio and are usually paired with audio cables. It can also refer to digital component video, which uses the color model YCbCr. Digital component video is capable of carrying signals, such as 480i, 480p, 720p, 1080i, and 1080p. See also YUV.

composer – a person who writes music, especially one who writes music as a professional. People who create musical compositions for orchestral and classical music are often called composers while writers of popular music and traditional music are often called songwriters, but this is not strict usage.

composite – (1) To combine the best segments of several takes of a performance into one really good performance. (2) A performance created by combining the best portions of several takes of a performance. Called comp for short. See also playlist.

composite equalization – the effective overall tonal balance achieved when an audio signal passes through two or more equalizers in series.

composite print – a film print that contains both picture and sound.

composite track – the track onto which the best segments of several takes of a performance are placed to form one complete and continuous performance. Also called a comp track. See also comping.

composite video – a video signal in which all the video information is combined into a single analog line-level signal in contrast to component video, in which the video signal is transmitted as three separate signals. Neither component nor composite video carries any audio and are usually paired with audio cables. See also YUV.

compositing – see comping.

compound – the mixture of PVC and other additives used in the vinyl mastering process to make vinyl records.

compound chord – see slash chord.

compress – (1) To reduce the dynamic range of an audio signal using a compressor. See dynamic range compression. (2) To reduce the size of a data file is reduced by eliminating redundant information, useless information, or data determined by various algorithms to be unnecessary. See data compression.

compression – (1) The portion of a sound wave in which air molecules are pressed together forming an area of higher pressure. The opposite of rarefactions. See diagram at right. (2) Dynamic range compression). (3) Data compression. Note:  All three of these definitions of compression are very different processes and care should be taken not to get them confused, especially dynamic range compression and data compression. The term audio compression is often used to refer to both dynamic range compression and data compression of an audio signal, which can lead to some confusion. A better choice would be to use the term dynamic range compression.

compression driver – a small specialized diaphragm, usually made of a metal such as aluminum, neodymium, or berylium, used to generates sound in a horn-type loudspeaker. Compression drivers typically are about 10 times more efficient than direct-radiating cone loudspeakers. They are usually used as midrange and tweeter drivers.

compression molding – a process in which a platic material, usually preheated, is placed in a heated mold that is then closed, and heat and pressure are applied to force the material into contact with all areas of the mold. The process is used in the high-volume production of items such as vinyl records. See vinyl mastering.

compression ratio – (1) In a compressor, the ratio of change in input level to the change in output level that occurs above the threshold measured in decibels (dB). For example, for a 3:1 ratio the output level is reduced by 3 db for every 1 dB of change in input level above the threshold. Also called compression slope or slope for short. (2) In data compression, the ratio of the size of a compressed file compared to the origial file. For example, a compressed file with a 3:1 compression ratio is ⅔ the size of the uncompressed file.

compression slope – see compression ratio.

compressor – a device that reduces the dynamic range of an audio signal using dynamic range compression. There are five main controls on most compressors, although sometimes given other names: (a) threshold, (b) ratio, (c) attack, (d) release, and (e) makeup gain. There are several types of compressors, including tube compressor, VCA compressor, FET compressor, optical compressor, variable-mu compressor, PWM compressor, digital compressor, low-level compressor, and multiband compressor. Compressors are used for several reasons, most commonly for leveling an audio signal or for taming an occasional transient, but sometimes it is used creatively, such as using pumping to create a pulsating, rhythmic effect, often on drums.

comp track – (1) Short for composite track. (2) See playlist.

compulsory license – a license in that does not require permission from the rights holder in order to obtain a license. This principle is an exception to most laws governing intellectual property whereby the owner of intellectual property has the exclusive right to license or decline to license such works. In the US, compulsory licensing applies to mechanical licenses for music in which the user has to pay the statutory rate to obtain a license. In the UK, with a compulsory license, the rate is negotiable, but with a statutory license, the rate is fixed by law. The laws in other country vary.

computer – a digital computer is a device into which data is input in the form of digitized data that is manipulated or processed in some way based a program or sequence of instructions. Computers usually include a means to store data and have a built-in operating system (called logic circuitry) on microchips. See also analog computer.

computer architecture – (1) The rules and procedures that describe the functionality, organization and implementation of a computer system. (2) The capabilities and programming model of a computer. (3) The instruction set, logic design, and implementation of a computer system.

computer crash – see crash.

computer file – see file.

audio glitch – see glitch.

computer keyboard – see keyboard.

computer monitor – see monitor, definition #5.

computer network – see network.

computer optimization – configuring a computer to maximize its performance for certain tasks, especially for use as a digital audio workstation (DAW) in a recording studio. Optimization may include disabling background programs, disabling automatic program updates, implementing special graphics modes, and using separate drives for the system and for audio data storage.

computer program – see program, definitions #4 and #5.

concealment – a technique in which the value of a missing sample in a digital audio file is estimated by interpolating from the values on each side of the missing data.

concentric groove – the circular groove on a record that follows the lead-in groove and precedes the lead-out groove. Also called a finishing groove.

concert pitch – (1) The agreed reference frequency which assigns the frequency of 440 Hz for the note A above Middle C, notated as A = 440 or A440. Also called standfard pitch or international standard pitch. (2) The pitch in which C instruments are pitched, such as the piano, flute, or oboe.

concert tuba – see tuba.

condenser – an older term for a capacitor.

condenser microphone – a microphone consisting of a capacitor with one fixed plate (the back plate) and a second plate consisting of a very light and thin metallized material that forms the diaphragm, which responds to changes in pressure caused by variations in a sound wave. When the diaphragm vibrates, the distance between the two plates changes which changes the capacitance. A nearly constant static electrical charge is maintained on the capacitor using a voltage (called a polarizing voltage) supplied either by a battery in the mic or by external phantom power. As the capacitance changes, the amount of charge across the capacitor changes, creating a small current proportional to the sound wave. The current is amplified by the head amplifier to create an audio signal. A condenser mic typically has greater sensitivity and a wider frequency response than a dynamic microphone. Also called a capacitor microphone, but probably the more correct term is electrostatic microphone. See also RF condenser microphone and electret condenser microphone.

condensite – a thermosetting varnish that was once used in the manufacture of Edison Diamond Disc records. The records consisted of a disc consisting of a mixture of wood and flour with a layer of celluloid molded to the top and bottom. Condensite was applied to each side and the resulting disc was cured in a heated oven to create a blank record ready for the pressing process. Althought these discs were much quieter than shellac discs used by others, they suffered from cracking and delamination.

conductance (G) – the ability of an object to conduct electricity. It is the reciprocal of resistance and is the ratio of current to voltage. Although traditionally measured in mhos (ohm spelled backwards), the SI unit is siemens.

conductive – being capable of passing an electric current.

conductive coupling – see dc coupling.

conductivity (σ) – the property of a given material that indicates its ability to conduct an electric current. It is the reciprocal of electrical resistivity. Usually it is represented by the Greek letter σ (sigma), but sometimes by κ (kappa) or γ (gamma) are used. The SI unit of conductivity is siemens per meter (S/m). Conductance (G) for a material can be calculated from the equation G = σ × A /L, where σ is the conductivity, L is the length, and A is the cross-sectional area. Also called electrical conductivity or specific conductance.

conduction – (1) The process of transmitting electricity through a conductor due to a electrical potential between two points. (2) The process of transmitting a sound wave through a medium.

conductor – (1) Any material that is capable of passing an electic current. Opposite of insulator. (2) The wires within a cable designed to carry an electric signal. (3) A person who directs an orchestra or choir.

conductor ruler – see ruler.

cone – see speaker cone.

CONEQ^TM – CONvolution EQualization. The trademark used by Real Sound Lab for their automated equalization system that adjusts the EQ on studio monitors for the acoustics in a control room.

cone cry – see edge yowl.

cone loudspeaker – see moving coil loudspeaker.

cone tweeter – see tweeter.

confidence head – a playback head used to monitor recorded sound on a DAT, siimilar to the playback head on a tape machine.

configuration – (1) The way a computer is assembled—the specific arrangement of internal and external components, including hardware, software, and peripheral devices. (2) The way in which a software program, plug-in, or device is setup for a particular task. (3) A group of settings in a DAW, such as fader levels, effect types, send levels, and panning that can be saved and retrieved later. Also called a snapshot, scene, setup, or scene memory.

conga drum – a tall, narrow, low-toned drum from Africa played by beating with the hands. Also called a tumbadora.

conical stylus – a stylus with a tip shaped like a cone. Because it is simple to produce, it is more economical than an elliptical stylus. Also called a spherical stylus.

connected TV – see smart TV.

connection – see electrical connection.

connector – (1) A device for attaching two points on an electric c. (2) A device at the end of a cable or electric wire used to attach to another cable or device. Connectors can be used for audio, video, electric, or optical connections. Analog connectors often use shielded cables to inhibit radio frequency interference (RFI) and noise.

console – a device that houses the controls and wiring (signal paths) necessary for recording and mixing. Also called a mixing console, mixing board, mixing desk (mainly British), or board (informal). Most consoles used in professional recording studios were made by only a handful of manufacturers: Neve, SSL, API, EMI, Universal Audio, Trident, Helios, MCI, and Harrison. Compare with control surface.

console automation – see automation.

consolidate – to convert a track having several clips into a single contiguous file. No processing is performed during this process. Other DAWs refer to this process as bounce, merge, glue, or render.

consonance – in music, a sound that is not dissonant. However, the term is used to describe a gradation from the most consonant to the most dissonant sounds or intervals. The opposite extreme is dissonance.

consonant – musically pleasing and having good harmony.

constant angular velocity (CAV) – a disc driving scheme with a constant angular velocity (a constant rotational speed or constant number of revolutions per second). The LP is a CAV system operating at 33⅓ rpm. CDs and DVDs use constant linear velocity (CLV ).

constant-bandwidth equalizer – see constant-Q equalizer.

constant bandwidth filter – a bandpass filter with a fixed-frequency bandwidth (expressed in hertz) no matter what the center frequency. Compare with constant-percentage bandwidth filter.

constant bitrate (CBR) – a type of codec in which the data is encoded and decoded at a constant rate, as opposed to a variable bitrate (VBR), where the bitrate varies with the complexity of the signal. See also average bitrate (ABR).

constant linear velocity (CLV) – a disc driving scheme in which the read/write mechanism is maintained at a constant velocity. A CLV drive must slow down the rotational speed of the disc as the reading/writing of data moves towards the outside of the disc because the linear velocity is greater there. CDs and DVDs use CLV, while LPs use a constant rotational velocity (constant angular velocity).

constant-percentage bandwidth filter – a bandpass filter whose bandwidth is a fixed percentage of the center frequency. The higher the center frequency, the wider the bandwidth. Compare with constant-bandwidth filter. Also called a constant percentage filter.

constant-percentage filter – see constant bandwidth filter.

constant-Q equalizer – a graphic and rotary equalizers in which the bandwidth (Q) remains constant during level boosts and cuts. Also called constant-bandwidth equalizer. See also proportional-Q equalizer.

constant rotational velocity – see constant angular velocity.

constructive interference – see phase reinforcement.

consumer audio – audio equipment manufactured for use primarily in the home. Although the quality may be similar, professional audio equipment is often more rugged and is designed to prevent interference from outside sources. See also consumer electronics.

consumer DIF – Consumer Digital Interface. See S/PDIF.

consumer electronics (CE) – electronic or digital equipment intended for use by consumers in private homes. Consumer electronics include devices used for entertainment (such as televisions, stereo equipment, and portable media players), communication devices (such as telephones and cell phones), and home-office products (such as desktop and laptop computers, printers, scanners, and paper shredders). Sometimes called home electronics.

Consumer Electronics Association (CEA) – a trade organization representing the consumer electronics industry. It began in 1924 as the Radio Manufacturers Association (RMA). In 1950, it changed its name to the Radio-Television Manufacturers Association (RTMA). In 1953, it became the Radio-Electronics-Television Manufacturers Association (RETMA). In 1957 it became the Electronic Industries Association (EIA), which changed to the Electronic Industries Alliance in 1998. In 1995, its consumer division, Consumer Electronics Group (CEG), became the Consumer Electronics Manufacturers Association (CEMA). In 1999, it changed its name to the Consumer Electronics Association (CEA), an independent division of EIA.

contact – see electrical contact.

contact cleaner – a cleaning agent, usually a non-flammable solvent, in an aerosol container used for cleaning electric contacts, connectors, components, and switches. A good cleaner removes dirt, oil, grease, and oxidation and leaves no residue. Also called an electrical contact cleaner or contact enhancer.

contact enhancer – see contact cleaner.

contact microphone – a type of microphone used to sense audio vibrations through solid objects, such as a table top. Unlike typical microphones that sense sound vibrations in air, contact mics are nearly insensitive to air vibrations sensing only sounds transmitted through solids. Although a contact mic has a different response from air microphones, its main advantages are that it is not affected by room acoustics and normally does not pick up sound (bleed) from adjacent instruments. See also piezoelectric microphone.

contact pickup – a transducer that converts sound waves in a dense medium, such as wood, metal, or plastic, into an audio signal, typically used on acoustic stringed instruments such as guitar, mandolin, and violin.

contact printing – the process of making a photographic or film print by placing the negative directly in contact with sensitized emulsion and exposing it to light. Compare with optical printing.

container file – see container format.

container format – a type of file format that can contain a variety of encoded audio, video, and other types of data. Container formats are essentially wrappers that do not specify what codec must be used, but rather it defines how the data is stored within the container. Examples of container formats include WAV, AVI, Ogg, and 3GP. Sometimes called a container file.

content – information or material, such as data, articles, reference materials, images, or music. Digital content is material that is available in digital form. Premium content is digital material that can be downloaded, streamed, or otherwise distributed on electronic media for a fee or by paid subscription, such as music, movies, TV shows, articles, audio books, and other items.

content creator data (CCD) – a method of encoding metadata for the multitrack, multi-session sound recordings used in the music industry. CCP was developed by BMS/Chace in cooperation with the Recording Academy, major record labels, and the Library of Congress.

content delivery – see digital distribution.

Content Delivery & Security Association (CDSA) – see Media & Entertainment Services Alliance.

Content ID™ – a system used by YouTube to detect copyright infringement in music used in videos. When found, YouTube usually appends an ad to the content and uses the revenue it receives to distribute fees to the rights holders.

continental pitch – See A440.

continuity – the condition in which an electrical circuit is continuously connected and able to conduct an electric current.

continuity tester – a device used to test if continuity is present in an electric circuit, wiring, or cable.

continuous controller (CC) – a category of MIDI messages which are used to convey performance or patch data for parameters other than those with dedicated message types (such as note on, note off, aftertouch, and pitch bend). Although there are 128 possible controller numbers, six are reserved for special purposes, making 122 available. The original MIDI standard assigned meanings to only a handful of these, such as volume (#7), pan (#10), slider position (#6), and mod wheel (#1), but subsequent revisions have assigned many more.

continuous sync – a process in which a DAW creates a new clock based on incoming SMPTE timecodes when recording to the DAW from a tape machine. The sample rate of the DAW varies continuously to stay in sync with the timecode variations. Continuous sync requires dedicated hardware and is not available on all DAWS.

continuous wave (CW) – (1) An electromagnetic wave with constant amplitude and frequency. (2) An early method of radio transmission, in which a carrier wave was switched on and off. By the varying duration of the on and off periods of the signal, information could be transmitted using Morse code. Reginald Fressenden first used continuous waves in 1902. Before that radio transmissions were intermittent damped waves, which were generated by spark-gap transmitters. These were not suitable for voice transmission. Fressenden first used a carbon arc in a resonant transmitter circuit, which was noisy and ineffficient. Later he developed a high-frequency alternator to generate the carrier signal.

contour generator – see envelope generator.

contrabass – see double bass.

contralto – (1) A type of classical vocal range being the lowest female voice type and the lowest tessitura, usually a range from about the F below middle C to the second F above middle C (F3 to F5). Contralto is similar to, but different from alto, being almost identical to countertenor. The contralto vocal range is fairly rare. (2) The musical range between soprano and tenor. (3) A singer whose voice is within this range. (4) A vocal part written in this range.

control board – another name for a console.

controlled image design – a control room design which uses angled surfaces and absorbers to control reverberations and reflections. This design does not require flush-mounted monitors. Because the sound quality is poor at places other than the designated listening point, absorbers are sometimes added to the rear wall. Compare with LEDE, ESS, non-environment, and RFZ designs.

Controlled Magnetic^® microphone – the trade marked name given by Shure for a dynamic microphone design that was a precursor to the moving coil microphone. It functions when sound vibrations move a diaphragm attached to a ferrous rod suspended inside a magnet causing a an electrical signal to be generated. This design is used in the Shure 520, nicknamed the “Green Bullet,” a favorite of harmonica players because of its limited frequency response of 100 Hz to 9 kHZ, which naturally reduces the harshness found at higher frequencies. Also called a controlled reluctance microphone. They are often abbreviated as CM and CR.

controlled reluctance microphone – see Controlled Magnetic microphone.

controller – (1) A device that generates a signal sent to the control input of another device. (2) A device that generates a MIDI signal to control other devices, such as synthesizers, samplers, or sound modules.

control grid – see grid, definition #2.

control room – the room in a recording studio that houses most of the equipment and in which the engineer controls and monitors the recording process.

control room design – a method of using a combination of geometry and/or acoustic treatment in a recording studio control room to provide a flat frequency response and a good stereo image, without reverberations and reflections that alter the sound. There are several design approaches, including ESS, LEDE, RFZ, non-environment, and controlled image designs.

control room mix – the rough mix that is used during a recording session and played in the control room. Sometimes this is the same mix as the monitor mix sent to the musicians, but often the monitor mix is customized to meet the musicians needs.

control signal – a pulse or frequency of electricity or light that represents a control command sent over a network, a channel, or radio frequency.

control surface – a component that interfaces with a computer and is used to control the functions of a digital audio workstation (DAW). Having sliders, knobs, and buttons, it performs like a smaller version of a console, but a control surface differs from a console or mixer in that it does not manipulate any sound, it only sends data to the computer software so that the sliders, knobs, and button move similar virtual sliders, knobs, and buttons in the DAW. However, it is usually easier to use than a mouse and keyboard. Some control surfaces can function as either a control surface or a console.

control track – (1) A track on a multitrack tape machine used for recording control signals for automation data sent to the console during mixdown. (2) A track on video recorders with a pilot tone that marks the start of each video frame in order to synchronize playback speed.

control voltage (CV) – an analog method of controlling synthesizers, drum machines, and other devices with external sequencers. The control voltage is usually used to control pitch and other parameters. A gate signal controls notes on and off. These methods have mostly been replaced by MIDI. Sometimes called control voltage/gate (CV/gate).

control voltage/gate (CV/gate) – see control voltage.

conventional current flow – see current flow.

conversion latency – the latency that occurs during the A/D and D/A conversion—the delay that occurs between the time that audio is presented to the A/D Converter and the time the data is presented to the output of the converter. Delays depend on how long it takes to measure the sample, to perform any processing or filtering, and to transmit the result to the output of the converter. Also called pipeline delay.

converter – see AD/DA converter.

convolution – a mathematical function derived from two given functions by integration that expresses how the shape of one is modified by the other.

convolution reverb – a method of digitally simulating the reverberation of an actual physical space using a mathematical model (convolution). For a particular concert hall or venue being emulated, an impulse (the sound of a starter pistol or a popping balloon) is created and the response (the resulting reverberations) is recorded and analyzed to create an impulse response (IR). The IR is then used to create reverb effects that are much more realistic than conventional algorithmic reverb. Convolution reverb can be either hardware or software. Besides the IR files that come with it, impulse response files for other venues can be downloaded from third parties and can be loaded into a compatible convolution playback device.

Cool Edit Pro – former name for Adobe Audition.

coprocessor – a secondary microchip or board that reduces the load on a computer's CPU or provides additional functionality to the CPU. Used with a DAW, a DSP coprocessor provides dedicated DSP power for running plugins, freeing the CPU to operate only the DAW. See also DSP accelerator.

copy – (1) A script used by voice over artist. (2) To make a duplicate of an audio file or other work. See cut and paste. (3) A duplicate made of an audio file or other work.

copy and paste – the process of using a DAW or sound editor to copy and move (paste) sections of recorded audio to a new location in the track or to other tracks, in a fashion similar to using “copy and paste” in a word processor. Copy and paste is often used interchageably with cut and paste, although technically cut and paste means the copied data has been removed, while with copy and paste the data remains intact.

copy bit – see SCMS.

copy code – a method proposed by CBS in 1982 to prevent digital copying of compact discs. A sharp 3.8-kHz notch was placed in the frequency response of the CD. A circuit in DAT recorders was designed to detect the notch and prevent copying of a CD when the code was detected. Although CBS claimed the notch was inaudible, most audiophiles disagreed and the system was never adopted.

copy protection – a method either by means of software or hardware to prevent copying of software, music, videos, and other intellectual property. There are a variety of schemes employed to accomplish this.

copyright – (1) The exclusive legal right, given to an originator or an assignee by a government entity for a specified period of time to reproduce, publish, distribute, or sell a literary, artistic, or musical work, or to authorize others to do the same. In the United States, copyright law is governed by the US Copyright Act of 1976. (2) Frequently used incorrectly as a verb to secure a copyright for a literary, artistic, or musical work. Technically, copyright should never be used as a verb since it means the right to copy. The correct use is to “obtain or secure a copyright.” For more detailed information, see the article on Copyrights, Royalties, and Permissions.

Copyright Act – see US Copyright Act.

copyright holder – (1) The author or originator of a work that is protected by copyright. (2) The employer of the author or originator of a protected work under a work for hire arrangement. (3) The person to whom an author or originator of a copyrighted work transfers ownership of the copyright using a written assignment of copyright. Note: Copyright ownership and ownership of the material object in which the copyrighted work is embodied are two entirely separate legal entities. For example, one person can own a manuscript, but another person own the copyright on the contents of the manuscript. See also rights holder.

copyright infringement – see infringement.

copyright law – see US Copyright Act.

copyright sign – see copyright symbol.

copyright symbol – the symbol used to designate a copyright. For everything other than a sound recording, © (a circled capital letter “C”) is used. In music, copyright of the lyrics, melody, chords, etc. would use this symbol. For sound recordings, ℗ (a circled capital letter “P”) is used. Also called a copyright sign.

copywriter – a person who writes scripts to be used by voice over artist.

cordless microphone – see wireless microphone.

core – (1) An individual processor within a CPU. Originally CPUs had only a single core. In the early 2000s, manufacturers began combining more processors onto a single microchip, in order to increase CPU speed at a lower cost. Most computers today have multiple cores. The more cores a processor has, the more instructions the processor can receive and process simultaneously, making the computer faster and more efficient. Also called a processor core. (2) A transformer core. (3) The conductors within a cable, which can be either solid core or stranded. (4) Can refer to core audio.

core audio – a set of services and drivers used to implement audio and music on Apple's Mac OS X and iOS operating systems. Similar to ASIO for PCs.

core audio format (CAF) – the container format for storing audio data developed by Apple, using the .caf extenstion. Designed to overcome limitations of older digital audio formats, including AIFF and WAV, a .caf container can hold nearly any type of audio format, and is not limited to a 4-GB size like older formats. Although it was originally a Mac-only format, there are now Windows applications that can open and convert CAF files to Windows formats.

core saturation – see transformer saturation.

Corey/Martin tree technique – a surround sound microphone technique designed by Jason Corey and Geoff Martin consisting of three subcardioid microphones facing the front, and two cardioid microphones facing the ceiling. The distance between the left and right front mics is 120 cm (48 in) with the center mic halfway between them. The rear surround cardioids are 30 cm (12 in) apart and about 60 cm (24 in) behind the front pair. The center microphone can be moved forward up to 15 cm (6 in), if needed. These distances can be adjusted depending on the size of the ensemble being recorded. A front spacing of 120 cm (48 in) is used for smaller ensembles, increasing to 180 cm (6 ft) for larger groups. However, with wider spacing the three front channels become more incoherent. See also wide cardioid surround array.

corner frequency – see cutoff frequency.

cornet – a brass musical instrument having a flared bell, tubing looped to form a straight-sided coil, and three valves. A cornet is similar to a trumpet, but it is shorter and wider. It is typically used in bands.

corrective EQ – the boost or reduction of a problem frequency range in an audio signal using an equalizer to remove bleed, noise, feedback, imbalances, and other problems that may degrade a mix or an audio signal. Compare with surgical EQ.

cough button – a switch that temporarily stops the tranmission or recording of a radio program when an on-air announcer has to cough.

coulomb – the unit of electric charge, equal to the quantity of electricity transferred in one second by a current of one ampere. It takes approximately 6.24 x 10¹⁸ electrons to make one coulomb of charge, which means each electron has 1.602 x 10^‑19 coulombs of charge.

counter electromotive force (CEMF) – see back electromotive force.

counter EMF – see back electromotive force.

counter hoop – see rim.

counterpoise – the portion of an antenna that balances the radiating element and acts as a ground. Although not always apparent, every antenna has a counterpoise and it affects the antenna efficiency. It usually consists of an array of metallic wires, rods, or tubes arranged around or under the antenna. The counterpoise functions as one plate of a large capacitor, with the conductive layers of the earth being the other plate.

countertenor – (1) The highest vocal range of the adult male voice, usually a range from the G below middle C to about D or E one octave above middle C (G3 to D5 or E5). The countertenor range is approximately equivalent to the contralto range. (2) The musical range between contralto or alto and tenor. (3) A singer whose voice is within this range. (4) A vocal or instrumental part written in this range.

count in – see count off.

count off – several beats before the music begins, used to establish the tempo and the starting point for the musicians. It can be tones or clicks of a click track, taps on a drum, or verbally counted off by one of the musicians. Sometimes called a count in.

coupling – (1) Transferring energy from one medium (such as a metallic wire or an optical fiber) to another medium or from one part of a circuit to another. Coupling may occur through physical contact, inductive, electrostatic, and other means. There are two types of electrical coupling: (a) ac coupling (also called alternating coupling or capacitive coupling) allows only ac signals to pass through the connection. It removes the dc offset by using a capacitor in series with the signal. (b) dc coupling (also called direct coupling) allows both ac and dc signals to pass through a connection. The dc component is a 0 Hz signal, which is the offset about which the ac component of the signal fluctuates. (2) See mechanical coupling.

coupling capacitor – a capacitor used between stages in a guitar amplifier that blocks the dc plate voltage of the previous stage and passes the ac guitar signal through.

counterpoint – (1) In music, one or more independent melodies added above or below the existing melody. (2) The technique of combining two or more melodies in such a way that they establish a harmonic relationship while retaining their individuality. (3) A composition that contains a counterpoint.

cover – (1) A new performance or recording of a previously recorded and released song made by someone other than the original artist. It may or may not be in the style of the original version. Also called a cover song or cover version. (2) To record or perform a previously recorded and released song.

cover song – see cover.

cover version – see cover.

coverage angle – see acceptance angle.

coverage area – the useful working area of a microphone as determined by the acceptance angle (coverage angle).

cowbell – a percussion instrument resembling the bell hung around a cow's neck to help locate it, but usually of heavier construction, without a clapper, and struck with a stick.

CPC – Circuit Protective Conductor.

cps – (1) Centimeters Per Second. The speed of recording tape as it moves past the tape heads, usually specified in inches per second (ips). (2) Cycles Per Second. The measurement of frequency. One cycle per second is one hertz (Hz).

CPU – Central Processing Unit.

C-QUAM – Capitible QUadrature Amplitude Modulation. A method of broadcasting stereo on the AM radio band, in which two carrier waves are broadcast simultaneously with the second, called a quadrature carrier, being 90 degrees out of phase with the regular carrier, which carries the sum of the two stereo channels, while the quadrature carrier carries the stereo difference signal. Special receivers are required to separate the signals into two stereo channels. A mono receiver receives only the regular carrier. This technique does not require any more bandwidth than a regular AM station. Also called quadrature amplitude modulation (QAM).

CR – Control Room.

Creative Voice Format – see VOC format.

crackle – intermittent moderate clicking, such as that found on an overly-played vinyl record.

crash – a serious computer failure, in which either the computer stops working properly or a program aborts unexpectedly. A crash is usually caused by either a hardware malfunction or a software bug.

crash cymbal – a a type of cymbal that produces a sharp, loud sound used primarily for accents.

CRC – see Cyclic Redundancy Code.

crescendo – (1) A gradual increase in the loudness of a section of music. (2) A musical symbol resembling a long “V” laying on its side and pointing to the left that indicates an increase in loudness. The opposite of decrescendo.

crest – see wave crest.

crest factor – the ratio of the peak value to the RMS value of a signal. A crest factor of 1 indicates no peaks (that is, a straight dc signal). A sine wave has a crest factor of 1.414 while a triangle wave has a factor of 1.732.

crimp terminal – a solderless connector in which the stripped end of stranded wire is inserted into a round or U-shaped channel of the terminal, which is then compressed around the wire. Crimp terminals can accommodate a variety of sizes and styles of connectors, such as banana plugs, spade connectors, ring connectors, and many more.

crisp – a descriptive term for a sound with good high-frequency response that provides presence. Compare with bright.

critical band – the range of audio frequencies within which a second tone will interfere with the perception of a first tone by auditory masking of the human ear. Although the critical bandwidth varies with frequency, it is usually between ↋ and ⅔ of an octave.

critical bandwidth – see critical band.

critical damping – the minimum amount of damping for a vibrating system to return to its normal position without oscillation. See also dynamic amplification factor.

critical distance (dc) – the distance from a sound source to the point where the sound pressure level (SPL) of a direct sound (D) and the sound pressure level of the reverberant sound (R) are equal. It is the distance from the sound source at which the direct-to-reverberant ratio (DRR) equals 1 (D = R).

CR microphone – see Controlled Magnetic microphone.

crocodile clip – see alligator clip.

cross-delayed echo – a technique developed by Decca in which the reverb for left instruments was placed on the right and vice versa.

crossed pair – see coincident pair.

crossfade – the gradual decrease in level of one track or audio signal as the level of another track or audio signal gradually increases creating a smooth transition from one to the other. Sometimes abbreviated as X-fade.

crossfader – a slider device that adjusts the levels between two audio signals. Sometimes abbreviated as X-fader.

crossfeed – the process of blending the signals of the left and right channels of stereo headphones, to reduce the “sound-in-the-middle-of-the-head” effect or to make the headphones sound more natural. Crossfeed can be introduced by the design of the headphones or a switch found on some headphone amplifiers.

cross-hand – a piano playing technique in which one hand reaches over the other, so that the right hand plays lower keys than the left hand.

cross modulation – intermodulation that produces unwanted frequencies that are equal to the sum or difference of a desired and an undesired frequency or of their harmonics.

cross modulation synthesis – see FM synthesis.

crossover – (1) An electronic circuit designed to separate and send sounds of particular range of frequencies to the correct driver in a speaker system, such as high frequencies to a tweeter and low frequencies to a a woofer. Because it is difficult to design a driver to accurately reproduce sound over the entire audible frequency range, two or more drivers are usually used. Using a crossover to split the audio signal into multiple frequency ranges with each band sent to a dedicated driver, allows the speaker system to reproduce the audible range more efficiently and with better fidelity. Crossovers can be divided into two groups: (a) active crossover (requiring power and containing amplification and sometimes called an electronic crossover) and (b) passive crossover (requiring no external power and without amplification). Active crossovers are more efficient than passive crossovers. The frequency at which the sound is divided is called the crossover frequency. Also called a crossover network. (2) An electronic circuit designed to split an audio signal into bands for use in multiband processing, in which each band can be processed (equalized, compressed, etc.) individually and then mixed back together again. The frequency at which the sound is divided is called the crossover frequency. Also called a crossover network. (3) An artist or song that appeals to fans of two or more genres of music. For example, country song that hits big on the pop charts would be a crossover hit.

crossover distortion – a type of distortion created when an audio signal crosses the zero line changing from positive to negative or negative to positive that occurs with some types of amplifiers (Class B) and other devices. It is not related to the audio crossover. Also called zero-crossing distortion.

crossover frequency – (1) The frequency separating two bands in a crossover network. (2) In a room, the Schroeder frequency.

crossover network – see crossover.

cross stick – a drumming technique in which the tip of the drumstick is placed about halfway across the drum head with the other end extending over the rim and the shaft of the stick is struck against the rim opposite the tip creating a high-pitched “click” similar to a wood block. Sometimes called a rimclick, but different from the rim shot. Not to be confused with cross-sticking.

cross-sticking – a drumming technique in which one hand is crossed over the other to move from one drum to another. Not to be confused with the cross stick technique.

crosstalk – (1) The unintended leakage of a signal from one channel into an adjacent or neaby channel, due to poor channel separation. (2) Another term for bleed.

crotchet – see quarter note.

CRT – Cathode Ray Tube.

crunch – an electric guitar tone with some distortion, a good deal of punch, and lots of presence.

crystal – (1) A solid body having a characteristic symetrical internal structure with definite and characteristic angles. (2) A small crystal (definition #1), often made of quartz, used to stabilize an operating frequency. The natural vibrations of the quartz provides an extremely stable frequency that can be used by the circuitry to establish very accurately the operating frequency for transmitters, receivers, oscillators, and clock signals.

crystal cartridge – see phonograph cartridge.

crystal-controlled – (1) Using an tranmitter operating frequency that is created using a quartz crystal, rather than using a frequency synthesizer. (2) Commonly used to describe devices that can operate on only one fixed frequency, rather than a number of synthesized frequencies.

crystal microphone – a microphone that converts sound into electrical energy by using a piezoelectric crystal. Also called a ceramic microphone, piezoelectric microphone, or piezo mic for short.

crystal oscillator – an electronic circuit that uses the resonance of a vibrating crystal to create an electrical signal with a very precise frequency.

crystal radio – an early type of radio receiver that used a galena (lead sulfide) crystal as a detector to separate the audio signal from the radio signal. It needed no power source as it obtained its power from the radio waves. Headphones were used to listen to the audio. Stations were tuned by placing a long wire (called a cat's whisker) at various places on the crystal. Also called a crystal set or cat's whisker receiver.

crystal set – see crystal radio.

CSA – Canadian Standards Association. A not-for-profit standards organization, composed of representatives from industry, government, and consumer groups, that develops standards and publishes them in print and electronic form.

CSMA/CA – Carrier sense multiple access with collision avoidance. A method of transmitting digital data in computer networks that avoids collision of data by sensing when the channel is idle.

Csound – a computer programming language for audio written in the computer language C, used to build instruments and patches.

CT-aacPlus – see High Efficiency Advanced Audio Encoding.

C-taper – see taper.

CT-HE-AAC – see High Efficiency Advanced Audio Encoding.

CTL (control track longitudinal) timecode – Control Track Longitudinal timecode. A timecode developed by JVC in the early 1990s for striping SMPTE timecode onto videotape. CTL timecode embeds SMPTE timecode in the control track area of helical scan video recordings similar to the way VITC timecode is embedded in the vertical interval area of a video signal, saving space by not using space on the precious audio track.

cu – Compliance Unit. See compliance.

Cubase – a digital audio workstation developed by Steinberg. It is one of the oldest DAWs still in widespread use, having originally been developed in 1989 for use on the Atari ST computer.

cue – (1) A signal or tone sent to musicians, engineers, actors, and others to indicate the start of something. Cues are often sent to musicians via headphones to indicate the beginning of a recording. (2) Setting a tape, record, disc, or other recorded medium so that it will immediately play from a specific point when started, usually the beginning of a song. (3) The point from which playback or recording begins according to a setting set in a digital audio workstation or tape recorder. (4) The title and composer of a piece of music as shown on a cue sheet. (5) Soundtrack music that is played for a specific scene or event in a film. See also cue point. (6) Short for a cue send.

cue box – see headphone amplifier.

cue list – a chronological list of program events with their start and end times used during audio mixing, editing, and film scoring. Sometimes used interchangeably with cue sheet. Also called an edit decision list.

cue mix – see headphone mix.

cue mixer – a submixer in a mixing console used to create a headphone mix to send to musicians in the studio.

cue mode – see edit mode.

cue point – a specific part of a movie soundtrack that corresponds to a visual event in the film. Also called a hit point or cue.

cue send – the bus on a mixer, console, or DAW used to provide a headphone mix to musicians in the studio. Called a cue for short.

cue send control – an adjustment on a mixer, console, or DAW used to control the level of the signal going to the cue send.

cue sheet – a chronological log containing a written synopsis of the music used in a production of a play, a television program, or a movie. It includes information such as song title, writer, publisher, and duration. The production team submits cue sheets to the PROs so they can track the use and broadcast of the music they represent. This can be done quarterly, semi-annually or annually. Cue sheets make it possible for composers and publishers to be compensated for their work. Sometimes used interchangeably with cue list.

cue system – a monitoring system used to provide a headphone mix to musicians in the studio. Called the cue for short.

cup mute – see mute.

current (I) – (1). The flow of electrons through a conductor. See current flow. (2) The rate of flow of electricity, as measured in amperes. The relationship between the voltage (V), resistance (R), and current (I) is V = IR, which is known as Ohm's Law.

current flow – current flows when electrons move from the negative terminal, through the circuit, to the positive terminal of the source. However, when electricity was first discovered, it was said that current flowed from the positive terminal, through the circuit, to the negative terminal. While this was incorrect, the terminology has survived and is sometimes designated as conventional current flow.

current limiting – a function or circuit found in some amplifiers that imposes an upper limit on the current delivered to an output to protect the amplifier and output devices in the event of a low load impedance, a short circuit, or other problem.

current spike – see transient voltage.

cut – (1) To reduce the level, amplitude, or gain, especially when referring to reducing the level of a given frequency band with an equalizer. Opposite of boost. (2) A reduction in level, amplitude, or gain. (3) To mute. (4) To stop recording, especially when looping or doing ADR work. (5) One of several tracks on an album. Also called a band. (6) The song that occupies the band. (7) To produce the tracks on an master for a vinyl LP. (This may be done several times for the same record as the stamper wears out. Each time is referred to a new “cut.” (8) In movie production, the instruction to terminate the action and stop filming. (9) A particular edited version of a film. (10) To make a recording, as in the phrase, “to cut a record.” (11) To remove a piece of data or audio as in the process of cut and paste.

cut and paste – the process of using a DAW or sound editor to cut and move (paste) sections of recorded audio to a new location in the track or to other tracks, in a fashion similar to using “cut and paste” in a word processor. Cut and paste is often used interchageably with copy and paste, although cut and paste technically means the copied data has been removed, while with copy and paste the data remains intact.

cut common time – see cut time.

cut down – a very precisely timed portion of a piece of production music reduced to the size of a TV advertisement, typically 15, 30, or 60 seconds in length. Also called an edit.

cut effects – sound effects taken and edited from a sound library, rather than being recorded on a foley stage.

cut number – a number usually added as a suffix to a matrix number of a recording to indicate which cutting by a lathe was used to create a stamper in vinyl record production. Before the 1980s, new masters were cut because the stampers became worn or damaged. After that new technology, such as direct metal mastering (DMM) made it possible to make many copies of a master cut without recutting. Even so, different cut numbers may exist because a master may not pass quality control, a record is pressed in more than one plant or in more than one country (each will cut its own masters), or a record is re-issured. During much of the era of the 78-rpm record, before recording tape came into common use, recordings were cut directly to disc. Therefore, a new stamper would require a new take, and take numbers would be included in the matrix area.

cutoff frequency – the frequency at which a filter begins to take effect, the boundary between the passband and the stopband. It is frequently defined as the point at which the signal is attenuated by 3 dB (3-dB down point), but other criteria are sometimes used, such as the midpoint of the transition band—the range of frequencies between the passband and the stopband. At the cut-off frequency the voltage V has decreased to the value of 1/√ 2  = 0.7071 = 70.71% and the voltage level (dBV) has decreased by 20 × log (1/√ 2 ) = -3.0103 dB. For a band-pass filter, there is an upper and lower cutoff frequency. Also called a corner frequency, rolloff frequency, turnover frequency, break frequency, or half-power point (because 3 dB down represent the point of half power).

cutoff rate – the number of decibels (dB) per octave that a filter reduces the level above or below the cutoff frequency. Also called the rolloff rate, rolloff slope or cutoff slope.

cutoff slope – see cutoff rate.

cut switch – see mute button.

cutter – see sound editor, definition #1.

cutterhead – the assembly used in vinyl mastering to cut the groove in a master, consisting of a tiny, chisel-shaped stylus made of metal or gemstone that is driven by two small voice coils that vibrate to the sound being recorded. The stylus is very stiff and requires several hundred watts to drive the coils. The stylus is heated by a small coil of resistance heating wire to insure a smooth and noise-free cut.

cutterhead stylus – see cutting stylus.

cutter stylus – see cutting stylus.

cut time – a musical meter indicated by the time signature symbol of a C with a line through it, equivalent of 2/2 time. Also called alla breve (Italian for “at the breve”) or cut common time.

cutting engineer – the person who oversees the process of using a lathe to cut grooves into a master during the vinyl mastering process