Файл: Sound Tech Terms Dictionary.pdf

C

cadence:  A musical punctuation, indicating the end of an idea, or preparing the ground for
transition to a new one; essentially a juxtaposition of two chords.

calendering:  To reduce the asperities on the surface of a magnetic tape, the tape is squeezed
between large steel rollers, a manufacturing process called calendering.

Calrec Soundfield microphone:  See Soundfield microphone.

cancellation:  See phase cancellation.

canned:  Slang for pre-recorded, as opposed to live(3), music or visuals.

Cannon connector:  See XLR.

cans:  Headphones.

capacitance:  See impedance.

capacitor (C):  A device made up of two metallic plates separated by a dielectric (insulating
material).  Used to store electrical energy in the electrostatic field between the plates.  It pro-
duces an impedance to an alternating current.  Also called a condenser.

capo:  The beginning of a piece of music.  See D.C.

capstan:  In a tape machine, the tape is moved by the effect of friction between a rotating
motor-driven pillar, the capstan, and a pinchwheel, also called the capstan idler, that holds the
recording tape securely against the capstan when a tape transport is in record or play mode.
The capstan motor directly or indirectly drives the capstan and moves the tape past the heads.
The capstan itself may be the extended shaft of the capstan motor.

capsule:  In a microphone, the diaphragm or actual sound receptor, including, in various

types of mics, the moving coil, ribbon, permanent magnet, or fixed condenser plate, and the
housing in which these are mounted.

cardioid microphone:  A directional  microphone  with an acceptance angle that is most sensitive
to sounds coming from the front and sides, while rejecting sounds coming from the rear.
Called cardioid because the polar pattern of the microphone is roughly heart-shaped.  All di-
rectional mics have a proximity effect, whereby sound sources close to the mic will have an
exaggerated low-frequency response.  Supercardioids and hypercardioids are cardioids, but
with a trade-off in the rear lobe.  When using supercardioids and hypercardioids as sound
reinforcement mics, it is important to note that the maximum rejection is not directly behind
the mic as it is with a cardioid, but is off to the side between 110˚-126˚.  However, a pair of
hypercardioid microphones used as a stereo X-Y pair yields a very clean cardioid response
pattern.  See pressure gradient.

C

carrier:  (1) A signal that is constant in amplitude or frequency and can be modulated by
some other signal.  The carrier itself does not transmit any information; all of the intelligence
is in the modulation sidebands, which are in a band of frequencies on either side of the carrier
frequency.  Some signals, such as FM stereo, involve more than one carrier to encode the in-
formation, and the lower-frequency carrier is called a subcarrier.  The subcarrier is mixed
with parts of the audio signal and used to modulate the main carrier.  In the receiver, the
subcarrier is recovered by demodulation of the main carrier and then demodulated to re-
cover its signal.  See amplitude modulation, frequency modulation, frequency modulation.  (2) In
FM synthesis, the carrier is the operator at the bottom of a stack in an algorithm, through
which the composite effect of other modulating operators connected to it is heard.

cartridge:  (1) The needle assembly at the end of a phonograph tonearm.  (2) In broadcasting,
a short, looped tape usually used for recorded messages and/or commercials.

CAS:  Cinema Audio Society.  A Los Angeles-based organization of film and television
recording personnel, founded in 1966.

Cat. 43:  The Dolby Laboratories device that turns a Cat. No. 22 Dolby A-Type noise reduction
card into a 4-band “noise fighter.”  The precise frequencies of the bands are optimized for
production sound problems and differ from those used in standard noise reduction
applications.  In 1991, Dolby formally introduced SR–type noise reduction, called the
Cat. No. 430.

cathode:  The cathode in any electronic component, such as a silicon diode or a vacuum

tube, is the electrode normally connected to the negative voltage.

CAV:  Constant Angular Velocity:  In a mass storage device, such as a disk, CAV means that
the disk assembly rotates at a constant speed, i.e., the data rate will increase for the tracks
near the edge, and decrease for tracks near the center spindle.  As opposed to CLV.

CCCC:  See LCRS.

C.C.I.R.:  Comité Consultatif International Radio.  An international radio standards com-
mittee, whose recommended recording pre-emphasis and post-emphasis curves are standard on
all recorders in most European and some other countries.  The European analog to the NAB.

C

CD:  The CD sampling rate is 44.1kHz and there are 32 bits per sample, so the data rate of
the encoded analog data is 1.41Mbps, but the inclusion of parity, synch, and subcode bits
raises the real data rate to 4.3Mbps.  A CD will hold about 650 Mb, or about 74 minutes of
stereo, 16–bit audio.  The digital portion of the CD audio system is not stereophonic, but
sequential monaural.  See also Control and Display signals.  Compare with Direct Stream Digital.
The CD file format is defined by ISO 9660.  For more information on CD standards, please
see Sound on Sound, “Compact Disc Formats” by Mike Collins, January 1998.  See also
SACD. (Super Audio Compact Disc.)  The CD specification is specified in “books,” each
defining the standard for a particular type of CD:

Blue Book:

CD Data (CD Extra)

The latest of the books to appear, this specifies the CD Extra format,
designed to include CD-ROM data on a standard (audio, Red Book) CD.
A CD Extra is actually a multisession CD, containing the audio tracks in
its first session, followed by a data track in the second session, etc.

Red Book:

System Description Compact Disc Digital Audio (CD-DA)

CD-DA (Digital Audio)  Established in 1980 as the first of the books
which defined consumer audio on CD.  A Red Book CD may have up to
99 tracks; each track is divided into blocks of data called sectors; each
sector contains, in addition to audio data, EDC/ECC, and 98 control
bytes of PQ subcodes.

Yellow Book:

System Description Compact Disc Read-Only Memory (CD–ROM)

CD-ROM (Read Only Memory).  Yellow Book extends the Red Book
specification by adding two new track types:

CD-ROM Mode 1:  Storage of computer data
Mode 1 sectors include an improved ECC for Data.

CD-ROM Mode 2:  Compressed audio, video, picture data
Mode 2 (Forms 1 & 2) CD-ROM/XA (Extended Architecture) is used to
integrate computer data with compressed audio and/or video, includ-
ing Photo CD and Karaoke CD.

White Book:

System Description Compact Disc Bridge (CD-V)

Developed to cover the CD-V (Video) format, and supported by JVC,
Matsushita, Philips, and Sony.  These are a special kind of CD-ROM/XA
bridge disc that allows the play of films and music videos on a dedi-
cated CD-V player, or on a CD-i player equipped with a CD-V cartridge,
or a computer with a CD-ROM/XA drive, an MPEG-1 decoder, and host
playback application. The CD medium is modified to record video sig-
nals as well as digital stereo audio signals.  The video information is re-
corded in analog form rather than digital.  CD-V discs contain full-
screen, full-motion video and CD-quality audio, and are independent of
any broadcast standard, e.g., NTSC, PAL.

Green Book:

System Description Compact Disc Read-Only Memory Extended
Architecture (CD-ROM/XA)

C

Orange Book:

System Description Compact Disc Systems Part II: (CD–WO)

A digital standard for recordable, write-once CD.  The specification cov-
ers both disk-at-once and track-at-once.  Many older CD-ROM drives
cannot read multisession discs, however, these discs can be converted to
a Red/Yellow/Green Book disc by adding a TOC, allowing the disc to
be read by any CD player.

CD Single: 

A small CD-DA that can record 20 minutes of stereo music; it is 80mm
in diameter.

CD-DA:  

CD-Direct Access.  Software for writing audio data on hard disk onto a
CD-R, for example, Toast™ or Gear.™  Such packages create an unfin-
ished audio session in disc-at-once mode.  Digital audio tracks must first
be converted to a computer file format like .WAV or AIFF.

CD Extra:  

Formerly called CD Plus.  A solution to mixed-mode CDs, CD Extra in-
verts the track structure of Mixed Mode by creating two separate ses-
sions:  first audio, then data.  CD Extra is a part of the Blue Book stan-
dard, making Blue Book CDs fully compatible with the Red Book in that
Blue Book (data) CDs can be safely used on audio players.  The one
problem with CD Extra format discs is that its multisession format makes
it unusable by first-generation CD-ROM players.

CD-I:  

 (CD Interactive)  An extension of Yellow book, allowing discs to
contain a mix of audio and video, plus data which the user can control
interactively.  CD-I discs use Mode 2, Form 1 and Mode 2, Form 2 tracks
which, like CD-ROM/XA, enable computer data and compressed audio,
video, or pictures to be played back at the same time.  CD-I tracks
cannot be played on normal CD-ROM drives, but specialized CD-I
players can play audio CDs, CD+G, Photo CD, and with a CD-V
cartridge, Karaoke CD or CD-V discs.

CD + MIDI:  

A type of CD which includes both audio data and MIDI data, i.e., a re-
cording of both the sound of a musical performance, as well as the MIDI
data used to generate it.  This allows the user to “play with the perform-
ance” by choosing different patches, etc.  This requires a MIDI Out
socket on the CD player.

CD-R:  See CD.

CD Single:  

A small CD that can record 20 minutes of stereo music; it is 80mm in di-
ameter.

CD-V: 

 CD Video.  The CD medium modified to record video signals as well as
digital stereo audio signals.  The video information is recorded in analog
form, rather than digital, like a small laser disc.

CEDAR:  Computer Enhanced Digital Audio Restoration.  A British-developed system for
the restoration and preservation of old audio recordings.  See also NoNoise.

C

cent:  The smallest conventional unit of pitch deviation.  One hundred cents equal one half-
step.  In an instrument, a cent is a term used in discussing pitch resolution; one cent is good,
more than six cents is bad.  See half-step.

center detent:  A notched position in the range of a variable control, allowing the user to re-

turn the control to precisely that position, such as the midpoint between the left and right
channels in a balance control.  Use to denote the flat position on tone controls, etc.

center frequency:  The frequency that is boosted or attenuated most by the operation of any
parametric equalizer or other similar processing device or circuit.  See Q.

center tap:  In a transformer, the electrical midpoint of the windings, made accessible for ex-

ternal connection.  Used, for example, in delivering power to balanced line condenser micro-
phones.  See phantom power, Appendix B.

C-format:  The international standard format for professional 1” videotape equipment.  De-
veloped by Sony, and sometiines called S-format after that company’s name.  See B-format,
Betacam, VHS.

CG:  Computer Graphics.

chain: Also called iron.  An integrated system composed of separate audio and/or video re-
cording, processing, or playback circuits and/or devices which are used in conjunction with
one another to produce one output result.  See B-chain, program chain, signal chain, side chain.

change-over dots:  See projection.

change-over projection:  See projection.

channel:  An independently processed or recorded signal.  (1) An electrical signal path.  In
analog audio (such as a mixer), each channel consists of separate wired components.  In the
digital domain, channels may share wiring, kept separate through logical operations.  (2) A
system for independently addressing up to sixteen separate MIDI devices over a single MIDI
cable.  MIDI provides definitions for 16 channels which transmit not audio signals, but digi-
tal control signals for triggering synthesizers and other devices.  MIDI data are associated
with a particular channel by virtue of a Channel ID Number that is interwoven with other
MIDI data being recorded.  A track holds data that (depending on the sequencer) may or
may not be restricted to one MIDI channel.  MIDI’s 16-channel limitation has been overcome
by employing multiple independent MIDI ports that each route sixteen channels, offering
the possibility of hundreds of channels.  (3) The left or right signals of a stereo audio system,
or the left, right, center, surround and/or subwoofer signals of a multichannel system, such
as LCRS or 5.1.  (4) In film, A complete, self-sufficient recording setup.  A production channel
would include a recorder, mixer, microphones, headsets, etc.  A transfer channel would
include  a 1/4” tape deck, a 35mm mag recorder, a resolver, and a monitoring system.

channel assignment matrix:  In a recording console, the group of buttons or switches by
which the signal from any input channel can be assigned to one or more busses, and thereby
be sent to one or more tracks of the multitrack recorder.