Файл: Sound Tech Terms Dictionary.pdf

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submix:  The mixture of signals fed into a submaster control in a recording or sound reinforce-
ment console.  The submix is usually a mix of signals that remains constant over a period of
time, and it is convenient to control it as a single signal.  Also called submix bus, subgroup, or
mix group.

subsonic:  Literally, “under sound.”  Subsonic actually means “slower than sound.”  The
proper term for a signal having frequencies below the human hearing range is infrasonic.

subtractive synthesis:  The technique of arriving at a desired timbre by filtering waveforms rich
in harmonics.  Subtractive synthesis is the type generally used on analog synthesizers.  This
works well on good analogue synthesizers, but when used on samples, reducing the number
of harmonics usually just makes the sound flat and lifeless.  Also called analog synthesis.  See
additive synthesis, sound synthesis.

subwoofer:  A special type of loudspeaker designed to reproduce low frequency signals only,
usually a band approximately 10-150Hz.

sum:  The addition of several audio signals or variants of the same audio signal.  This is nor-

mally achieved at the inputs of an amplifier in a mixer.

summing amplifier:  See combining amplifier.

Super 35:  A widescreen film format that makes use of the full width of the 35mm film frame,
including the area normally occupied by the optical soundtrack.  Therefore, there can never be
any 35mm EK neg prints made from a Super 35 negative, requiring an interpositive from the
full-aperture original negative to be enlarged to an anamorphic internegative, where the result-
ing aspect ratio is 2.4:1.

Super-Bit Mapping™ (Direct™):  A type of dithering method for encoding DSD-format audio
information for playback on standard (16-bit) CDs.  Developed by Sony, the new version of
SBM, SBM Direct accepts a DSD input signal (16-bit PCM) and produce an output encoding
with a (claimed) 20-bit resolution through a one-pass noise-shaping/decimating process which
uses a very complex FIR reconstruction filter.  SBM Direct is being developed by Sony in an ef-
fort to make their SACD format successful against DVD-A, as SACD players will offer play-
back of conventionally recorded CDs with enhanced audio quality.  See also HDCD.

supercardioid microphone:  A variation on the cardioid microphone pick-up pattern which is
most sensitive at the front and sides, while rejecting sounds entering 135°-225˚ to the rear.  The
supercardioid has a unidirectional pattern narrower than a cardioid, but wider than a hypercar-
dioid.  Also called a cottage loaf mic in the UK.  See directional microphone.

Super Clock:  Digidesign’s proprietary version of word clock, used as a master clock for all
Digidesign interfaces.  Super Clock runs at 256 times the sample rate; word clock runs at the
sample rate.

supervising sound editor:  The person responsible for the sound editorial process on a film,
including dialog, Foley, and sound effects.

supply motor:  In a tape transport, the motor that establishes proper tape tension on the sup-
ply side of the capstan and drives the fast rewind mode.  Also called the rewind motor.

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supraaural:  Literally, “on top of the ear.”  This term refers to headsets that rest on the outer
ear.  They are necessarily light in weight and do not exclude external sounds very well.  The
opposite of circumaural.

surround channel:  A single audio channel that feeds multiple speakers, either on the walls of

a theater, or in a home surround system.  In practice, any format which does not have spilt sur-
rounds will be used for ambient sound only.

surround-sound:  Multichannel sound that is reproduced through three or more loudspeakers
above or behind, as well as in front of, the listener.  See 5.1, 7.1, Dolby Surround-sound, Logic 7,
AC-3, THX, transaural audio.

surround tracks:  In 35mm and 70mm projection from release prints with magnetic sound, one
or two of these tracks is amplified through speakers mounted at the sides, rear or on the ceil-
ing of the auditorium in order to produce surround-sound.

sustain:  (1) The third of the four segments in an ADSR envelope.  The sustain portion of the
envelope begins when the attack and decay portions have run their course, and continues until
the key is released.  The sustain control is used to determine the level at which the envelope
will remain until the note is released.  While the attack, decay, and release controls are rate con-
trols, the sustain control is a level control.  (2) A pedal fitted to pianos and some percussion in-
struments, such as the vibraphone, that is used to prevent notes from being damped, thus
lengthening their decay time, and therefore, not a true (infinite) sustain.  A pedal offering a
similar function is often available for synthesizers where, of course, an infinite sustain can be
achieved on some voices.  (3) A MIDI Controller Change message assigned to the parameter in
a synthesizer which reproduces the function described in sustain(2).

sustain loop:  A loop which cycles during the sustain segment of an envelope before the rest of
the sample plays.  See also release loop, loop.

sustain pedal:  The electronic equivalent of a piano’s damper pedal.  In most synthesizers, the

sustain pedal latches the envelopes of any currently playing or subsequently played notes at
their sustain levels, even if the keys are lifted.  Compare with sostenuto pedal.

SVA:  Stereo Variable Area.  A motion picture sound system consisting of two closely spaced
optical variable-area soundtracks on 35mm film.  Dolby improved this format with their Dolby-
A compander system to improve the SNR, as well as employing Scheiber matrixing to synthesize
a third (center) and fourth (surround) channel for surround-sound applications.  Most modern
movies with stereo soundtracks employ the Dolby SVA system.  See snake track.

swarf:  See chip(1).

sweep:  To vary a parameter or signal in real-time, such a smoothly varied sine wave from low
to high frequency to measure the frequency response of a device.

sweep EQ:  See parametric equalizer.

sweetening session:  A recording session in which a previously made recording is augmented
by the addition of other instruments.  See also overdub.

sweet spot:  The optimum position for a microphone to be placed in front of an instrument or
for a listener to sit, relative to near-field, or other area-focused, monitors.

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swell pedal:  A foot-operated control for synthesizers and electric organs that adjusts volume,
hence allowing the sound to “swell.”  Originally, a mechanical device on a pipe organ with a
similar purpose.

Swelltone™:  A brand of dubbing theater speaker system.

swept filter:  A type of filter where the frequency of the filter can be controlled electronically,
rather than being manipulated by the user.  An example of a swept filter is where a LFO could
be used to sweep the filter frequency up and down, or an envelope could be generated to shape
the filter sweep.

switched controller:  A type of Controller Change message which is used to induce some kind

of change between only two conditions, e.g., sustain pedal On or Off.  As opposed to a continu-
ous controller.

sync:  Synchronization.  (1) The process of time-locking a number of normally independent
and free-running systems.  Where one of these is a tape recorder, the term tape sync is used:
one track of the tape is used to carry a sync track which is used to provide timing for the other
devices.  Two devices are said to be “in sync” when they are locked together with respect to
time, so that the events generated by each of them will always fall into predictable time rela-
tionships.  See also SMPTE timecode, crystal sync, sel-sync, jam sync.  (2) The operating mode of
tape recorders that uses the sel-sync process of playback.  (3) In a synthesizer with two or more
oscillators, the ability to lock the frequency of the slave, to a master.  This has the effect of elimi-
nating the beating which can occur if one is slightly out of tune with respect to the other.  If the
slave’s frequency is adjusted higher than the master, there will be no actual change in fre-
quency, but an alteration in the harmonics, giving the composite sound a different timbre.  This
is most effective if the frequency of the slave is modulated constantly, perhaps with an envelope
generator, to produce a distinctive kind of wailing sound.

sync block:  A device used in editing to keep film and sprocketed soundtracks in sync.  It can

have two or more gangs of sprocketed wheels that rotate in unison and a counter that displays
a feet/ frame count from a selected starting point.  Also called a synchronizer.

sync head:  See sel-sync(2).

synchronization:  (1) The precise alignment of picture and sound during projection and play-
back such that visual and audio events will be reproduced with the same time relationships
they had when originally captured to tape.  (2) The process by which this is achieved.

synchronizer:  A separate device that reads timecodes recorded on two or more devices, com-
pares the timecodes, and adjusts the machines’ read/replay/write positions and speeds based
on the results of that comparison.

Synclavier:  The trade name of one of the earliest commercially available computer music in-

struments, implementing a type of FM synthesis.  Sequencing and monophonic sampling facili-
ties (at a sampling rate of 50kHz) were soon added.  The sampler was expanded into a full
hard-disk recording unit which coined the name Direct-to-Disk.  Towards the end of its devel-
opment, a Synclavier was an integrated system with ninety-six voices, sequencing, and multi-
track hard-disk recording, aimed at post-production and other professional users.

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sync-lock:  Sync-lock, also called phase-lock, emulates the old control track or pilot tone method
of synchronization.  The system reads the timecodes, synchronizes the transports, and takes
any deliberate offsets into account.  Once the system is locked, the slaves only use the speed in-
formation that is derived from the timecode.  Specific timecode addresses are ignored.  This
method allows the tape machines to stay locked even if the timecode relationships change.  See
chase-lock.

sync mark:  A mark that the editor places on the head leaders for the workprint and each track
of edited magnetic film.  These generally put all tracks in editorial sync with one another so that
they will maintain synchronization when reproduced on dubbers equipped with synchronous
motors.  The editor may also place a similar set of markings on the tail leaders of all reels of
picture and magnetic film, to check that there has been no slippage in projection or playback.

sync master:  See sync reference.

sync mode:  See sel-sync(1).

syncopation:  In music, the placing of accents on normally unaccented parts of the bar.  The ef-

fect is usually to anticipate the main beats.  See upbeat, downbeat.

syncope:  A term used to refer to the unnecessary proliferation of tied notes that can occur
when a notation module in a sequencer program reflects every rhythmic nuance of the per-
formance data.  The problem can often be ameliorated by an option which quantizes only the
appearance of the notated music.

sync pop:  A single film frame of 1kHz used a guide to synchronize the sound and picture.

The pop on the track negative creates a visual guide for the negative cutter who uses it to
make a printing start mark.  The pop occurs two seconds before the first frame of the picture,
and thus corresponds to the “2” frame on the SMPTE Universal leader.  On standard film
leader, the number at the pop is “3” because it counts down in actual film footage.

sync pulse:  (1) The output of a clock used to keep synchronous devices, such as tape and video

recorders, in synchronization.  (2) The signal recorded by the sync head of a Nagra, derived
from the camera motor through a sync cable, or from the Nagra’s own crystal sync generator.
See FM sync.

sync reference:  The sync pulse output by the sync master device, used by the synchronizer as
the reference signal for all interlocked devices in the recording and/or playback chain.  The sync
master may come from house sync or some other source which generates the master clock.

sync sound:  A soundtrack recorded for motion picture where the audio elements are recorded
synchronously with the picture.  The opposite of wild sound.

sync tone:  (1) In electronic drum machines and sequencers, a bi-phase modulated square wave
generated in the machine.  This can be recorded onto tape, and when played back into the ma-
chine, will sync its signal output with the tape.  Analogous to MTC and SMPTE timecode, but
differing in the frequencies and word lengths that various manufacturers use in their ma-
chines.  (2) The 60Hz pilot tone that motion picture cameras send to the Nagra or other sync re-
corder, and that controls the playback speed during transfer so that the magnetic film will sync
with the workprint.

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sync track:  A sync tone reference signal recorded onto magnetic tape or magnetic film.

sync word:  At the end of every 80-bit SMPTE timecode word is a 16-bit sync word.  The sync
word provides direction and sync-lock speed information, and marks the end of each timecode
word.  The bits are: 0011 1111 1111 1101.

synthesis:  The process of electronically creating sounds on a synthesizer.  The word synthesis
has the implication of combining separate elements into a new whole, and is therefore, not
necessarily to denote “synthetic” as in artificial.  See sound synthesis.

synthesizer:  A musical instrument that generates sound electronically and is designed ac-
cording to certain principles developed by Robert Moog and others in the 1960s.  A synthesizer
is distinguished from an electronic piano or electronic organ by the fact that its sounds can be
programmed by the user, and from a sampler by the fact that the sampler allows the user to
make digital recordings of external sound sources.  Synthesizers, particularly if provided with
MIDI software and hardware, need not have a keyboard, and most need to be connected to
amplification equipment if they are to be heard.  See also master keyboard, tone module.

syntonic comma:  The error arising in any just intonation, due to the fact that the octave is in-
compatible with the simple frequency ratios of the intervals of the diatonic scale.  If ƒ is the fre-
quency of the tonic C, the first sixth produces A, with a frequency of 

5

3

ƒ.  In going to D, an

interval of a fourth is required, and this is a frequency ratio of 

4

3

, so its frequency will be 

4

3

 of

A, which is 

5

3

 of ƒ, or 

4

3

×

5

3

ƒ, which is 

20

3

ƒ.  The descending fifth gives G, at a frequency

of

2

3

×

20

9

ƒ = 

40

27

ƒ.  The last fifth results in the tonic, C, with a frquency of 

2

3

×

40

27

ƒ =

80

81

ƒ.  This

discrepancy is called the syntonic comma, and is equal to about one-fourth of a half-step.  It
results in the fact that, after the above simple five-chord progression, the tonic is no longer at
the same frequency at which it started.  Intervals of major thirds are not commensurate with a
perfect fifth, the difference being the syntonic comma.  The following integer equation must,
therefore, be false for all integers:

X

n

Y

f

2

m

f

where X, Y, n, and m are integers, and ƒ is the frequency of the tonic.  The left-hand side
represents successive steps of musical intervals, and the right-hand side represents octave
transpositions.  It can be shown that this equation can never be satisfied.  See also the diatonic
comma.

System-Common:  A type of MIDI data used to control certain aspects of the operation of the
entire MIDI system.  System-Common messages include Song Position Pointer (SPP), Song Se-
lect, Tune Request, and End-of-System-Exclusive (EOX).

System-Exclusive (sys-ex or SysEx):  System-Exclusive is designed to be an open-ended part
of the MIDI specification, defined to enable the transmission of the entire memory contents of
a synthesizer over a MIDI cable.  This transmission is often called a bulk dump.  Sys-ex com-
mands are strings of numbers, usually written in hexadecimal format, that carry information
to a MIDI device, specific to the manufacturer and particular model.  In other words, that de-
vice, exclusively, will respond to the commands, and all other MIDI devices ignore them.  Sys-
ex data is used most commonly for sending patch parameter data to and from an editor/librarian
program, but other types of data such as the contents of tuning tables are transferred in this
way as well.  See SDS, SMDI.