Файл: Sound Tech Terms Dictionary.pdf

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APRS Tape-Label System:  The APRS has decided on a standard color-code for tape
labelling:

Type

Color

Details (Note:  A clone is digital and a copy is analog.)

Session Tape

blue

A multitrack or two-track work tape that may contain out-

takes.

Original Master

red

The first-generation of the final stereo product.  Not necessarily

suitable for production purposes.

Production Master

green

All necessary EQ and treatment has been applied to the

program 

material (vinyl, CD, cassette, DAT) for the format

indicated.  For 

example, a CD master would need further PQ-

encoding for the 

pressing process.

Production Master Copy

orange

If source and duplicate are digital, then the copy is a (CD,

DAT) 

clone.  If the duplicate is analog, the tape is a

copy and should not be 

duplicated further without the producer’s consent.

CD Tape Master

grey

Fully prepared and PQ-encoded tape for glass mastering

(original, 

digital clone).  Any clones generated must include

regenerated 

timecode and relaid PQ-encoding information.

Safety Copy

pink

Strictly for safety.  Not to be used without producers’

permission.

Not For Production

yellow

Identifies a tape that is not currently suitable for production.

Media Copy

yellow

Supplied for a specific medium and not for general production

or 

reproduction.  May also include timecode as detailed

on the box.

APT x100:  See ISDN.

A&R:  Artists and Repertoire.  The department of a record company that selects the per-

forming groups or artists who will be signed to the label, what songs or compositions each
artist will record, and who will work with the artist in the production, arranging, and per-
formance of the material in the production of master tapes.

aria:  Italian for air (song).  Generally indicates a composition for solo voice with
accompaniment, also by extension, a lyrical instrumental piece.

A-roll:  Film footage used to introduce or provide backup material for a live video broadcast.

arpeggio:  The playing of chord patterns by sounding each note in a sequence, rather than si-
multaneously.  An arpeggiator is a device which will automatically produce arpeggiation,
given the parameters which control Direction (up or down or random), a Hold button which
allows note patterns to be triggered which keep playing when the keys are released, and a
Range control which sets the group of notes to be played over.

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arrangement:  (1) A version of a piece of music for resources other than those originally
intended.  This may be an instrumental version of a vocal number, a piano reduction of an
orchestral piece, or may involve altering other parameters of the original, such as its
harmony, rhythm, or structure.  (2) In sequencers, a term sometimes used for the general
layout of tracks, channels and patches, rather than a complete song.  This template can often be
saved as a separate file.

articulation:  The way of characterizing notes (usually in a melody) by the precise control of
their individual lengths to produce or eliminate gaps between them.  The terms staccato and
legato reflect the two extremes of articulation.  It is one of the most important ways by which
music can be shaped into phrases.

ASCAP:  American Society of Composers, Authors, and Publishers.  The first performing-
rights organization formed in 1908, ASCAP collects fees for broadcast of recorded
compositions on radio and television, and for live public performances of music and
distributes payments to the copyright holders of these compositions.

ASCII:  American Standard Code for Information Interchange.  The most common encoding
for transmitting text data digitally.  The code employs 8-bit binary words, by which each
letter of the English language, numeral, and symbol is uniquely designated.

aspect ratio:  The width-to-height ratio of an image.  Specifically in film, the format that the
film image is intended to be shown in, most commonly expressed as width relative to height,
where the height parameter has been scaled to represent 1 unit.  Standard TV screens are
1.33:1, films shown in U.S. theatres are 1.85:1, anamorphic films are 2.4:1.  Ratios may also be
expressed as integers, e.g., the TV ratio may be expressed as 4x3, and widescreen TVs are
16x9, or an aspect ratio of 1.78:1.

asperity:  A small irregularity or imperfection in the surface of a magnetic tape.  Low-
frequency noise in analog tape recordings caused by asperities produce asperity noise in the
recording, a type of modulation noise in that the noise is manifested in the band immediately
above or below the program signal.  See calendering, dropout.

assemble editing:  Editing of an audio or video program by making a master copy of the
various takes, rather than physically splicing pieces of tape together.  Virtually all digital ed-
iting is done this way.  The opposite of insert editing.

assembly:  See copyediting.

assigns:  Push-buttons on the input modules of a control console that connect, or assign, that
particular input to any of the output busses of the console.  The signal is routed to the desired
tape track of the destination device usually by a matrix of switches in each module of the
mixing and/or recording console.  This routing process is known as assignment.

asynchronous:  Not according to a fixed rate of repetition.  An asynchronous signal can occur
at intervals which do not necessarily coincide with a fixed-rate system or master clock pulse.

ATA:  See IDE.

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ATF:  Automatic Track Following.  The system used by R-DAT players to ensure that the ro-
tary heads follow the recorded track.  This uses a set of signals that is recorded along with the
digital data and which are passed to the servo controls to ensure that the tape is correctly po-
sitioned with respect to the heads.

atmospherics:  See backgrounds.

ATR:  Audio Tape Recorder.  This is the analog version.  A digital audio tape recorder is
called a DTR.

ATRAC:  Adaptive TRansform Acoustic Coding.  A lossy, 5:1-formatsplit-band perceptual
coding and compression scheme for reducing data to be written on a MiniDisc.  ATRAC offers a
5:1 data reduction ratio in the case of MiniDisc, employing the equivalent of 52 filter bands
for spectral analysis and requantization.  Later versions of ATRAC vary the size of the sam-
ple blocks dynamically between 11.6ms and 1.45ms according to the input signal to allow for
temporal masking, providing extremely good resulting sound.

A-track:  The primary dialog track cut by the picture editor.  The B- and subsequent tracks

would be used for overdubs.

attack:  The first part of the sound of a note.  In a synthesizer envelope, the attack segment is
the segment during which the envelope rises from its initial value (usually zero) to the attack
(peak) level (often the maximum level for the envelope) at a rate determined by the attack
time parameter.  See ADSR.

attack time:  (1) The rate of attack of a note.  (2) The time it takes for a compressor or limiter to

reduce its gain after a strong signal is applied to it.  See release time.

attack transient:  The actual attack waveform.  See transient.

attenuation:  The reduction, typically by some controlled amount, of an electrical signal.

attenuator:  A potentiometer (pot or pad) that is used to adjust the amplitude of the signal
passing through it.  The amplitude can usually be set to any value between full (no attenua-
tion) and zero (infinite attenuation).  Pots can be either rotary or linear (sliders), may have
discrete dentents (more often in older equipment), and can be either hardware or virtual slid-
ers on a computer screen.

A-type:  See Dolby noise reduction:

AU (.AU):  An audio file format developed by Sun Microsystems, supported by some PC and

Mac audio programs.  This format supports stereo and mono files with either 8-bit or 16-bit
resolution.  It can encode linear files, or use µLaw or ADPCM compression.

audio:  Literally, “I hear” in Latin.  The term pertains to any signal, sound, waveform, etc.,
that can be heard, as opposed to subsonic or ultrasonic sound, radio-frequency signals or video
signals.

audio coding mode:  A parameter in Dolby Digital surround-sound format which refers to the
number of channels and their location in for form F/R, where F is the number of front chan-
nels and R is the number of rear channels.  For example, 5-channel surround is called 3/2
mode, stereo is 2/0, and mono is designated 1/0.

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audio enhancer:  Any dynamic signal processing device that in some sense improves a dull or
lifeless sound.  It can be a simple as EQ or a complex DSP algorithm.  Examples of exciters
are the Aphex Aural Exciter, BBE Sonic Maximizer, or SPL Vitalizer.  Enhancers combine dy-
namic equalization with either harmonic synthesis or phase manipulation.

audio frequency:  See AF.

audio silence:  A type of diagnostic recording made with the recording set-up as planned, but
with all faders down.  Used to make a reference measurement of the noise floor and/or a tape
of biased noise.

audio taper:  A type of potentiometer designed for use as a volume control in audio equipment

where the resistance varies in a logarithmic, rather than a linear, fashion with rotation of the
knob.  This gives a better correlation between control rotation and the subjective loudness of
the signal.

audio-to-MIDI:  Software or hardware that takes a monophonic instrumental or vocal line,
analyzes the pitches, amplitude, and timbre, and converts the line to MIDI notes, complete
with pitch-bend, MIDI velocity and volume, and possibly additional controller data.

AudioX:  An open MIDI driver specification/standard being promoted by Cakewalk™.

auditory masking:  See frequency masking, masking.

augmentation:  (1) The increase of a major or perfect interval by one half-step to make an
augmented interval.  (2) The appearance of a musical idea in note durations which are longer
than those used for its first appearance.  This technique was often used in the ployphonic
music of the middle ages and renaissance, as well as in contrapuntal music (e.g., fugues) of
the baroque and later periods.

aural:  Of, relating to, or perceived by the ear.

auto-assembly:  In on-line editing, the process by which the edit-programmer produces the
edited video master tape according to the instructions on the EDL, without human
intervention.  This is only possible where footage is consistently lit and exposed.

auto-correct:  See quantization.

auto-input:  One of the electronic operating modes of a multitrack recorder.  When auto-
input is selected, all channels will remain in sel-sync playback mode until the machine is
placed in record mode.  Any channels that are in ready status will then begin recording and will
automatically pass their input signals direct to their outputs.  When recording is stopped,
these channels return to sel-sync playback mode.  Also called stand-by mode.

autolocator:  A device for controlling the transport system of a tape recorder, allowing
timecode referencing such as SMPTE.  Usually a number of locate points can be stored by the
device.  Some sequencers have an autolocate facility.  Also called zero locate.

Automatic Volume Control:  See AVC.

Avid:  A brand of nonlinear video editing system, which, while not being exactly an industry
standard, is the most commonly used digital video editing system.

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automation:  A system where manual control of a process is replaced or enhanced by
computer control, such as mixing desk automation where faders, mutes, and equalization can
be controlled in part or in whole by a computer.  In write mode, the automation system
produces a continuous record of all the actual fader settings and adjustments made by the
engineer during a mix.  Most systems allow changes on replay, while remembering and
recreating previous manipulations of other tracks.  The level changes are recorded and
recreated by VCAs in each input module of the console.  The VCA-produced data can be
recorded directly onto a track of the multitrack tape, giving a continuous record of all
mixdown fader settings.  Or, the VCA outputs can be recorded onto a separate disk.  In the
latter system, alignment of the fader data with the multitrack master tape is achieve by
referring to a common SMPTE timecode recorded on the tape and disk systems.  See mute
mode, mute-write, null-point, read mode, snapshot automation, update mode, write mode.

autopanner:  A device for processing a signal so that it can be made to appear at various
positions in a stereo image via a remote control or MIDI commands.

aux or auxiliary:  An assignable, line-level input with no dedicated input source.  Generally
refers to an input connector in a preamplifier or integrated amplifier, signal processor, mixer,
effects device, etc.  The aux input has no de-emphasis or other special equalization and accepts
line-level signals.  Tone controls on a preamp usually also affect signals sent to the aux input.

auxiliary:  A bus allowing a signal to be sent from a mixing desk prior to the main output,
usually to provide an input to effects.  See effects send.

auxiliary envelope:  An extra envelope in a synthesizer that, instead of being hard-wired to a
filter or amplitude, is intended as a modulation source that can be applied to various destina-
tions.

auxiliary messages:  A classification of MIDI messages which includes Active Sensing, All
Notes Off, Local On/Off, and Reset, and which describes whether the particular MIDI device
responds to any of thsese messages.

aux section:  A smaller, independent mixer within the main mixing console which has an
output consisting of a mix of everything going into the channels on which the appropriate
effects send been turned up.

auxiliary send:  Also called aux send.  See effects send, insert point.

AVC:  Automatic Volume Control.  A circuit which adjusts the gain of an audio device in in-
verse proportion to the incoming signal level.  An example is a portable tape recorder which
is designed for speech recording; when the speaker is close to the microphone, the gain is re-
duced so as not to overload the tape.  Also, a circuit which increases a TV or radio receiver’s
gain when it is tuned to weak stations and decreases the gain when it is tuned to strong sta-
tions.  Called AGC (Automatic Gain Control) in TV.

AVI:  Audio Video Interleaved.  Microsoft’s answer to Apple’s QuickTime, and not compati-
ble with Macs.