Файл: Sound Tech Terms Dictionary.pdf

D

dry:  Consisting entirely of the original, unprocessed sound.  The output of an effects divide
is 100% dry when only the input signal is being heard, with none of the effects created by the
processor itself.  Lacking in reverberation.  Compare with wet, flat.

dry/wet balance:  This refers to the amount of dry signal relative to the amount of reverb or

other effect-processed (wet) sound.

D.S.:  Dal Signo.  “Play from the sign( ).”

DS4:  The name of the original Dolby Laboratories recording/monitoring unit used by re-

recording stages during a Dolby Stereo mix.  Prior to the 2-track print master, the unit is used
for 4:2:4 monitoring purposes, encoding a 4-channel composite mix into two tracks and then
decoding it back into four channels.  Later versions of these units include the SEU4 and
SDU4 units which offer, respectively, the ability to encode and decode print masters,
although without either the container of the optical track simulation featured in the DS4.  The
DS10 contains a magneto-optical recorder for theatrical Dolby Digital mixes and also records
the Lt–Rt SR-encoded print master.  None of the above units can be purchased; their use is
free for films that have paid for the appropriate license fee and/or trademark agreement.

DS10:  See DS4.

DSD:  See Direct Stream Digital.

DSP:  Digital Signal Processor.  Broadly speaking, all changes in sound that are produced
within a digital audio device, other than changes caused by simple cutting and pasting of
sections of a waveform, are created through DSP.  A digital reverb is a typical DSP device.

DST:  See Direct Stream Transfer.

D-sub(miniature) connector:  Also called a D-connector, or a D-type connector.  A type of

connector commonly found on computers and data transmission devices, including SCSI
devices and computer monitors.  D-type connectors have a “D-shaped” angled housing, and
have 9-, 15-, and 25-pin configurations, designated DE-9, DA-15, and DB-25, respectively.

DTL:  Direct Time Lock.  An early MIDI synchronization system developed by MOTU.  See
MTC.

DTR:  Digital Tape Recorder.  This is the analog version.  An analog audio tape recorder is
called an ATR.

DTRS:  A 16-bit format used on Tascam and Sony MDMs, providing up to 108 minutes of
16-bit, 8-track record time on an NTSC-120 Hi-8mm videocasette.  See ADAT.

D

DTS:  Digital Theater Systems. A 5.1-format theater surround-sound system which uses six
discrete analog channels and perceptual encoding scheme for surround-sound on a CD-ROM
interlocked to either a 35mm or a 70mm print with timecode.  Lossless.  The DTS codec pro-
vides for data rates from 256kbps to 1536kbps, focusing on 1141kbps as the optimum for
transparent sound quality.  DTS was originally developed for the film industry, however,
there are a number of CD titles currently released in DTS format.  A DTS CD carries six
channels of digital audio in 5.1 format in 20-bit words at a 44.1kHz sample rate, with a com-
pression ratio of about 3:1.  An additional decoder is needed to play a DTS CD on a standard
CD player. .  First used in 1993 for the film, “Jurassic Park.”  See also Dolby Digital, Dolby Ste-
reo.

DTS Stereo:  See stereo optical print.

DTV:  Digital TeleVision.  DTV’s audio specification provides up to six discrete channels of
5.1–format audio, where the LFE channel is  band-limited to 25Hz-120Hz.  DTV has been
developed specifically for the home theater market, as an improvement to the ProLogic sys-
tem.

D-type (connector):  See D-sub(miniature) connector.

dub:  (1) (verb)  In the most general sense, to dub is “to copy,” although in film sound it has
many similar meanings.  Dub can refer to the act of replacing dialog, usually via ADR, either
in the original language or in a foreign language. (2) Dubbing is also the common name for
re-recording.

Dub-A, Dub-B, Dub-C:  See ProDigital.

dubber:  Film sound term for a playback-only mag machine.  These were previously known
as dummies.  See digital dubber.

dubbing:  (1) The act of re-recording sound effects, location sound, music, dialog, and/or Foley.
Usually used to refer to the substitution of a foreign language or other replacement for the
original dialog track in a film or TV production.  (2) The process of making a copy or copies
of a recorded analog or digital original.  (3) To mix together onto a single track all of the
separate edited soundtracks of a film or television production.  See re-recording, dubbing thea-
ter.  See transfer.

dub masters:  See final mix.

dub stage:  See dubbing theater.

D

dubbing theater:  Also called a dub stage.  A special studio where music is blended with
dialog and sound effects for the final soundtrack.  A dubbing theater is actually a small
movie theater, with a large screen and full theater surround system.  A row of seats is re-
moved from the middle of the theater and a large mixing console specially designed for film
sound is put in place.  There is also a machine room which houses dubbers and projectors,
isolating the noise from the recording studio in which the DME stems can be recorded in
sync with film projected on a screen visible through a window.  The screen hangs in a thea-
ter equipped with the mixing console which controls the sounds played back by all the dub-
bers, other prerecorded sources, and the sounds being recorded in the studio.  The theater
itself is designed to approximate the acoustics of a public cinema.  Also called mixing studio,
re-recording studio, re-recording stage, or theater.

duck:  (verb) To lower the level of music to accommodate dialogue or other sound effects.

dummy load:  A high-power resistor that is connected to the output of a power amplifier to
make the amplifier function as though it had a loudspeaker connected to it.  A dummy load
circuit can be used to test amplifier performance as it would perform when connected to
loudspeakers, or in a device such as a speaker simulator so that the amplifier always sees a
high-impedance load at the output stage, even if no loudspeaker is connected.

dump edit:  See edit switch.

duo-bilateral:  The technical term for the variable area optical soundtrack format used on all
35mm mono and stereo soundtracks.  See SVA, Dolby Stereo, DTS Stereo.

duplet:  A pair of notes (or rests) executed in the time normally taken by three of the same
value, most commonly occurring in compound-time music.  The inverse of a triplet.  See time
signature.

duration value:  The duration of a note is strictly a result of the time difference between
when a given MIDI Note-On message is recorded and when a Note-Off message with the
same note number is recorded.  If a duration value is changed, it will result in the change of
the time when the Note-Off message is transmitted.  If the note start time is modified, both
the Note-On and Note-Off times will be moved forward or backward by the same amount.

duty cycle:  In a pulse wave, where immediate transitions occur between the high and low
levels, mark is the time in one cycle occupied by the high level, while space is the time in the
same cycle occupied by the low level.  The ratio of mark to the whole determines the timbre
of the sound represented by the saveform.  Also called the mark/space ratio.  See also pulse
wave, square wave, Appendix C.

D

DVD:  Digital Video (Versatile) Disc.  A new multiple media format agreed upon by Sony,
Philips, Toshiba, and others.  DVDs are the same size as a CD, only with a higher track and
pit density.  The first, single-sided DVDs will hold 4.7Gb; as double-sided, multi-layer discs
are available, the capacity will be 8.5Gb and 17Gb, respectively.  Transfer rates are about
1.35Mbps, or about as fast as an 8X CD-ROM drive.  The data format is 24-bit 96kHz.  One
DVD is sufficient to store a typical movie, eight tracks of Dolby AC-3 surround audio, and
numerous subtitle tracks, which is why the film industry is pushing it: an improvement in
the potential of both audio and video quality with the profit profile of a CD.  One DVD-5
disc will allow 318 minutes of 48kHz, 20-bit, two-channel audio, or about 144 minutes of
88.2kHz, 24-bit, two-channel audio.  At 88.2kHz, 24-bit, LCR plus two channels of 44.1kHz,
20-bit surround-sound, a DVD-5 will hold 75 minutes of audio.

DVD players will be able to play back CDs, but not those written using the CD-R standard.
As with CD-ROM formats, DVD specifications are referred to in terms of books, A-E:

A:

DVD-Video
DVD-A:  Audio Only
DVD-AV:  Audio-Video, contains a subset of DVD-V

B:

DVD-Data

C:

DVD-Audio

D:

DVD-R (write-once)

E:

DVD-RAM (rewritable)

Additional DVD subdesignations are:

V:

DVD-Video

VAN: DVD-VAN (video disc, audio-enabled)
5:

Single-layer DVD (4.7Gb)

9:

Dual-layer low-density (8.5Gb)

18:

Dual-layer high-density  (17Gb)

The new DVD-A standard allows for up to six channels of audio.  With DVD-V, audio must
be recorded at a 96kHz sampling rate, while the DVD-A standard supports 44.1kHz,
88.2kHz, 176.4 and 192kHz sampling rates.  The DVD-A specification has two parts: DVD-A
(audio only) and DVD-AV.  DVD-AV contains a subset of the DVD-V specification to in-
clude real-time text, full-screen video, and other MPEG options.  DVD-A has an Audio Man-
ager, while, not surprisingly, DVD-V has a Video Manager.  If a DVD-A has video titles, it is
an –AV disc.  The multiple viewing angle feature of DVD-V is not supported in the –AV
specification.  A working specification for DVD-VAN, a bridge format between DVD-V and
DVD-A formats which will enable a DVD-V disc to be playable on a DVD-A player, if so
authored.

D

The DVD-A specification includes optional formats for DTS, Dolby Digital, lossless compres-
sion, MPEG-2 BC (Backward Compatible), and DSD, and 

provides for two “channel groups”

which is a method for signal partitioning, roughly equivalent to front and rear (six-channel
maximum unless otherwise noted):

Channel Group 1

Channel Group 2

Number of Channels

1 to 4

0 to 3

Sample Rate (kHz)

44.1

44.1

48

48

88.2

88.2 or 44.1

96

96 or 48

176.4 (2 channels max.)
192 (2 channels max.)

Word Length (bits)

16

16

20

16 or 20

24

16, 20, or 24

dynamic allocation:  See dynamic voice allocation.

dynamic effect:  (1) An effect which alters the loudness characteristics of a signal without in-
troducing any timbre changes.  The most common dynamic effects are compression and limit-
ing.  (2) Some companies use the term dynamic effects to refer to effects devices whose proc-
essing parameters can be controlled in real-time via MIDI.

dynamic equalization:  Equalization where the amount of boost or cut varies according to

the dynamics and spectral content of the signal being processed.  Dynamic equalization is
most often used in audio enhancers.

dynamic filter:  (1) An early type of single-ended noise reduction system that uses one or two
filters whose rolloff frequencies are controlled by the level of the signal.  As the high-
frequency signal level falls during soft passages, the high-frequency response is reduced;
when the signal level is high, the full bandwidth is restored.  (2) A circuit used in aural excit-
ers where a side-chain signal is combined with some dry signal in such a way that the origi-
nal signal is modified both additively and subtractively to create the impression of an in-
crease in both bass and brightness and the mid-range appears more focused.  This type of
spectral shaping is designed to be closely related to the way the human hearing system
changes at different listening levels.  See equal loudness curves.

dynamic headroom:  The ability of a power amplifier to handle short bursts of power with-
out overload.

dynamic loudspeaker:  See loudspeaker.

dynamic microphone:  In a dynamic microphone, a moving coil in a magnetic field to gener-

ate electricity.  Two types of dynamic microphones are the moving coil and ribbon.  (Moving
coil mics are typically referred to as dynamic mics, while ribbon mics seem to be called ribbon
mics.)  Dynamic mics have a rougher response than condensers or ribbons, and can be used
to soften fine detail in the recorded sound.  A well-designed moving-coil dynamic mic can
handle very loud sound without distortion, and so is preferred for miking guitar amps and
drums.  Dynamic mics also have a pronounced presence peak that gives the sound an edge or
punch.