Audio Terminology And Definitions Dictionary
C Symbol for capacitance and centigrade.
Cantilever Arm on which is fitted the stylus of a
Capacitance A measure of reactance (units: Farad, pF, uF etc).
Capacitor Solid state device used in electronic circuits and loudspeaker crossover networks to introduce a
required level of capacitance.
Cartridge The small component fitted to the front end of a tonearm. Contains the stylus and electro- magnetic
system required to track a vinyl record (LP or single) and feed output to an amplifier phono stage. There are two main types of hi-fi pickup cartridge - the 'moving magnet' and 'moving coil'.
Cassette Audio cassette or analogue cassette. Contains blank or pre-recorded tape on spools constrained
within a case or cassette.
Cassette Deck The machine required to play and/or record onto an audio cassette.
Angular Velocity) Laserdisc operating format in which the disc rotates at a
constant speed during play. CAV permits more special effects (still-frame,
slowmotion, and fastmotion, for example), but this format is somewhat wasteful
of disc space. CAV discs are limited to thirty minutes of material on each side
of a 12-inch laser disc. (See also: CLV.)
(Constant Bitrate) CBR
encoding uses roughly the same amount of memory to encode both the simple and
complex passages of a source file. Thus, the user is likely to experience
audible or visible loss of quality during complex parts, especially with lower
bitrate files. Most newer audio and video codecs employ a technology known as
variable-bitrate (VBR) encoding, which allows resulting files to look and sound
better while still retaining a compressed, convenient file size. In contrast to
CBR, VBR encoding assigns more bits to the complexly detailed portions of the
original source and fewer bits to the simpler portions.
Disc) Different formats of CDs are used for various
applications. For example, CD-DA (Compact Disc–Digital Audio) is used for
music, and CD-R and CD-RW (recordable formats) are used for data.
CDi Compact Disc Interactive. An offshoot technology
from CD, developed by Philips as an educational and entertainment format providing interactive still and moving
pictures and audio sound.
Disc—Read Only Memory) Refers to both the media and the format for storing
digital data (computer files or music information) on compact discs. Because of
its high information density, an ordinary CD-ROM can be used to store up to
680MB of digital information.
Center Channel In
a multi-channel home theater system, the center channel is primarily responsible
for conveying on-screen dialog. Depending on how a movie or TV broadcast was
originally recorded and the method used to bring the sound from studio to home,
the center channel usually carries well over 60 to 75 percent of the sound we
Center Channel Speaker
The speaker in a multi-channel home theater system that is placed midway between
the main left and right speakers at the front of the main listening/viewing
area. The center channel speaker is most often placed just above or
below a display, or it can be concealed directly behind an acoustically
transparent screen if used with a two-piece projection system. Center channel
speakers reproduce, as you might expect, center channel information only.
A surround sound encoding/decoding format developed and marketed by SRS Labs. It
processes audio data differently than Dolby or DTS codecs with the intention of
providing a more immersive sonic experience.
signal-altering condition that occurs when an amplifier cannot accurately
amplify the shape of the input signal because of current and voltage
limitations. When viewed on an oscilloscope, a clipped signal shows substantial
flattening of both positive and negative peaks, almost as if these peaks had
been "clipped off" by a pair of shears. A clipped signal contains large
amounts of harmonic distortion and can be more damaging to loudspeakers than an
undistorted signal of equal or even greater power.
Linear Velocity) Laserdisc operating format in which the rotational speed
of the disc varies as the laser pickup travels from the inner edge to the outer
edge of the disc. This maintains a constant velocity of data past the laser
pickup and allows more efficient use of disc space, resulting in sixty minutes
of material on each side of a 12-inch laser disc. The downside of CLV compared
to CAV is that CLV does not allow the special effects capabilities of the CAV
format. CLV is also the operating format for compact discs. (See also: CAV.)
A method for compressing and decompressing digital files (co-dec). Each codec
uses a slightly different set of algorithms to accomplish this goal.
A relatively indefinite term that describes unwanted alteration (i.e.,
distortion) of the original signal. Speakers are more likely to "color" the
sound than are other components.
Compact Disc The first commercially available digital
audio playback format. Software is a 12cm diameter single sided silver disc containing digitally encoded signal to a 44.1kHz, 16-bit standard. Optical playback is by means of laser beam. Developed jointly by Philips
and Sony CD has spawned a number of offshoot audio/video technologies such as CDi and
Compliance A measure of the springiness in a component. A cantilever suspension, moving coil
speaker drive unit suspension, CD player isolation feet etc.
Component Video Connection
A type of video connection in which the distinct color and black-and-white
elements of the signal are transferred via separate cables from a source to a
video display. Three RCA cables with red, green, and blue connections are used.
There are two types of component video connections in use for consumers:
· Y,Pb,Pr: progressive scan–capable component
video input/output connection
· Y,Cb,Cr: interlaced scan–only component video
(See also: Y, Pb, Pr
and Y, Cb, Cr.)
Composite Video Connection
A connection in which both the color
(chrominance) and black-and-white (luminance) portions of a video signal are
transferred via a single RCA video cable, usually one with yellow connectors. A
composite video connection is inferior in quality to a component video
A way of reducing the storage requirements, transmission time, or both of
digital data. Compression can be either "lossy" (i.e., some data is
irretrievably thrown out during the process) or "lossless" (the recovered
data is a bit-for-bit replica of the original).
Container Format A file
structure that holds different kinds of data within a single file. Container
formats (e.g., RealAudio and TIFF) are gaining popularity because of their
multimedia applications and their cross-platform compatibility. For example, a
single container file can hold chapter information, hyperlinks, and subtitles,
as well as different kinds of codecs that enable various types of players to
read the file.
Continuous Calibration Designed
by Philips, continuous calibration is a low-bit D/A converter with a constant
weighing circuit that keeps the D/A process linear and improves resolution.
Contrast ratio is the difference between the brightest whites and the blackest
blacks that a video display device can deliver. There are several methods of
defining contrast ratios, and specific numbers can rarely be compared without
referring to the measurement method used. Look for "native" or ANSI
(American National Standards Institute) specifications rather than "dynamic"
circuit (technically, a superposition of at least two filters) that divides an
audio signal into parts above and below what is often known as the "corner
frequency" or "crossover frequency." The rate at which a crossover divides
the spectrum is called the "slope."
If you see a crossover described as "400 Hz @ 18
dB/octave," the crossover's corner frequency is 400 Hz. The low-pass filter
reduces high-frequency output by 18 dB one octave below
that point, and the high-pass filter reduces low-frequency output by 18 dB one
octave above that mark.
Crossovers usually are used to separate a wide-range audio
signal into more narrow-range components so that each component may be safely
directed to specialized loudspeaker drivers (woofers, tweeters, etc.) for
optimum reproduction. Crossovers are usually categorized by their complexity
(two-way, three-way, four-way, etc.).
crossovers are categorized as "passive" or "active." Passive crossovers
(sometimes called "high-level" crossovers) are usually found inside
loudspeaker enclosures. They divide the audio signal after it has been amplified
and send the different portions to the appropriate loudspeaker system drivers.
Active crossovers (sometimes called "electronic" or "line-level"
crossovers) divide the signal prior to amplification and thus require separate
amplifiers for each frequency segment. Active crossovers are more precise, but
usually they are more costly to implement correctly. Powered subwoofers may use
either active or passive crossovers.
Per Second More commonly known as Hertz (abbr: Hz) after the German who discovered
the nature of audio frequencies. It is the speed of movement of a sine wave or cycle that determines its frequency, and in turn the musical pitch of a note..