Surround sound specifications

For the following sections, a distinction is madeside left (L) and side right (R).
between the number of discrete channels encoded inOne channel for both surround speakers at the rear -
the original signal, and the number of channels that aremono surround channel (S).
reproduced for playback; these can be added usingOne low-frequency channel using a sub-woofer (LFE).
matrix decoding. A distinction is also made betweenDescribes the Dolby Digital EX discrete/matrixed
the number of channels reproduced for playback, andhybrid Surround system. Source media, usually DVD is
the number of speakers over which these channelsoften branded with "Dolby Digital EX" logo.
are played. Graphics to the right of each sectionSurround Sound speaker placement: (8 speakers in
represent the number of channels, not the number oftotal) Surround Sound speaker placement is different
speakers used.for both music and movie content.
Additionally, 4.1, 5.1, 6.1, and 7.1 formats make use ofFor music speakers placement is unknown
bass management, which allows sound that is belowFor movie surround, the front speakers should be
the abilities of main channels (5.0 channels) to beplaced at the edges of the screen, toed in to face the
redirected to the subwoofer, which is designed tocentral listening location, and the tweeters should be
handle that frequency range. There are notationear height. The center speaker should be placed
differences between the pre-bass-managed signal andbehind the screen (when using projection) or over or
once it has passed through bass manager. Forunder a tv, and as close to ear high as possible. Side
example, in 5.1, the channels are referred to as L(eft),channel speakers should be placed high on side walls,
R(ight), C(enter), L(ow )F(requency)E(effects),to the left and right of the listening position, equidistant
S(urround)L(eft), and S(urround)R(ight). However, oncefrom the front speakers and the rear speakers. Rear
passing through the bass manager, they are referredchannel speakers should be placed high on side walls,
to as L(eft), R(ight), C(enter), Sub(woofer),slightly behind the listening position, and should have a
S(urround)L(eft), and S(urround)R(ight).nomal hi quality monopolar construction.
3.0 Channel Surround (analog matrixed: Surround)6.1 Channel Surround (digital discrete: DTS-ES)
Extracts 3 audio channels from a stereo source:Delivers 6 audio channels and 1 LFE channel from a 7
Two channels for speakers at the front - left (L) andchannel source:
right (R).Two channels for speakers at the front - left (LF) and
One channel for surround speaker at the rear -right (RF).
surround (S).One channel for speaker at the center - center (C).
Describes the numerous matrixed pre PrologicTwo channels for surround speakers at the sides -
Surround processors.side left (L) and side right (R).
Speaker placement: (3 speakers in total) ThreeOne channel for both surround speakers at the rear -
identical speakers placed equidistant around a centralmono surround channel (S).
listening position.One low-frequency channel using a sub-woofer (LFE).
4.0 Channel Surround (analog matrixed: Quadraphonic)Describes the DTS ES discrete Surround system.
Extracts 4 audio channels from a stereo source:Source media, usually DVD is often branded with
Two channels for speakers at the front - left (L) and"DTS ES" logo.
right (R).Surround Sound speaker placement: (8 speakers in
Two channels for surround speakers at the rear -total) Surround Sound speaker placement is different
surround left (LS) and surround right (RS).for both music and movie content.
Describes the early matrixed Surround Quadraphonic,For music speakers placement is unknown
Quadraphonic Stereo system. Source media, usuallyFor movie surround, the front speakers should be
records or tape is often branded 4 channel stereo.placed at the edges of the screen, toed in to face the
Speaker placement: (4 speakers in total) The frontcentral listening location, and the tweeters should be
speakers should be placed at the edges of the screen,ear height. The center speaker should be placed
toed in to face the central listening location, and thebehind the screen (when using projection) or over or
tweeters should be ear height. Rear channel speakerunder a tv, and as close to ear high as possible. Side
should be placed high on the back wall, slightly behindchannel speakers should be placed high on side walls,
the listening position, and can be of smaller size, due toto the left and right of the listening position, equidistant
the frequency limitations of the surround channel.from the front speakers and the rear speakers. Rear
4.1 Channel Surround (analog matrixed: Dolby Prologic)channel speakers should be placed high on side walls,
Extracts 4 audio channels, and 1 LFE channel from aslightly behind the listening position, and should have a
stereo source:nomal hi quality monopolar construction.
Two channels for speakers at the front - left (L) and7.1 Channel Surround (digital discrete: Dolby Digital Plus,
right (R).DTS-HD)
One channel for speaker at the center - center (C).Delivers 7 audio channels and 1 LFE channel from an 8
One channel for both surround speakers at the rear -channel source:
mono surround channel (S).Two channels for speakers at the front - left (LF) and
One low-frequency channel using a sub-woofer (LFE).right (RF).
Describes the Dolby Prologic matrixed SurroundOne channel for speaker at the center - center (C).
system. Source media, usually VHS, Laserdisc orTwo channels for surround speakers at the sides -
television broadcast, CableTV/Satellite is oftenside left (L) and side right (R).
branded with "Dolby Surround" logo.Two channels for surround speakers at the rear -
Surround Sound speaker placement: (6 speakers insurround left (LS) and surround right (RS).
total) The front speakers should be placed at theOne low-frequency channel using a sub-woofer (LFE).
edges of the screen, toed in to face the centralDescribes the Dolby Digital Plus discrete Surround
listening location, and the tweeters should be ear height.system. Source media, usually HD-DVD and
The center speaker should be placed behind thesometimes Blu-Ray is often branded with "Dolby Digital
screen (when using projection) or over or under a tv,Plus" and/or DTS-HD logos.
and as close to ear high as possible. Rear channelSurround Sound speaker placement: (8 speakers in
speakers should be placed high on side walls, slightlytotal) Surround Sound speaker placement is different
behind the listening position, and should be of bi-polefor both music and movie content.
construction, due to the frequency limitations of theFor music speakers placement is unknown
surround channel.For movie surround, the front speakers should be
5.1 Channel Surround (analog matrixed: Dolby Prologic II)placed at the edges of the screen, toed in to face the
Extracts 5 audio channels and 1 LFE channel from acentral listening location, and the tweeters should be
specially encoded stereo source:ear height. The center speaker should be placed
Two channels for speakers at the front - left (L) andbehind the screen (when using projection) or over or
right (R).under a tv, and as close to ear high as possible. Side
One channel for speaker at the center - center (C).channel speakers should be placed high on side walls,
Two channels for surround speakers at the rear -to the left and right of the listening position, equidistant
surround left (LS) and surround right (RS).from the front speakers and the rear speakers. Rear
One low-frequency channel using a sub-woofer (LFE).channel speakers should be placed high on side walls,
Describes the Dolby Prologic II matrixed Surroundslightly behind the listening position, and should have a
system. Source media, usually PS2 or Gamecube isnomal hi quality monopolar construction.
often branded with "Pro-Logic II" logo.8 Channel Surround (digital discrete: Dolby Digital HD,
Surround Sound speaker placement: (5 speakers inDTS-HD Master Audio)
total) The front speakers should be placed at theDolby Digital HD and DTS-HD Master Audio are
edges of the screen, toed in to face the centralemerging 8 channel home surround systems currently
listening location, and the tweeters should be ear height.supported by HD-DVD and Blu-Ray DVD. Currently
The center speaker should be placed behind thethere are no consumer receivers on the market
screen (when using projection) or over or under a tv,supporting either DD-HD or DTS-HD MA, supported
and as close to ear high as possible. Rear channelreceivers may be released as soon as the first half of
speakers should be placed high on side walls, slightly2007. It is not clear at this time whether these
behind the listening position, and should have a normalreceivers will be 8 channels or 8.1 channels.
hi quality monopolar construction.Cinematic 8 channel audio is a commercial surround
5.1 Channel Surround (digital discrete: Dolby Digital, DTS)sound standard that adds two speakers to the more
Delivers 5 audio channels and 1 LFE channel from a 6conventional, and consumer-oriented 6-channel (5.1)
channel source:audio set-up. 8-channel positional audio utilizes the
Two channels for speakers at the front - left (L) andstandard front, center, and LFE (bass) speaker
right (R).configuration, but in addition, includes two speakers
One channel for speaker at the center - center (C).positioned by the side and two by the backside. Using
Two channels for surround speakers at the rear -such a sound configuration, almost every angle of
surround left (LS) and surround right (RS).sound can, theoretically, be captured for a completely
One low-frequency channel using a sub-woofer (LFE).immersive experience.
Describes the Dolby Digital and DTS SurroundBut the 8-channel format has another, even more
systems. Source media, usually DVD and sometimeswell-established tradition. The history of 'electronic
Laserdisc or satellite/digital cable is often branded withmusic' includes the evolution of multi-channel playback
"Dolby Digital" and/or DTS logos.in concert (arguably the real roots of 'surround sound'
DTS uses a higher sampling rate than Dolby Digital,for cinema) and for a considerable time the 8-channel
thus DTS uses less compression and achieves higherformat was a de facto standard. This standardisation
fidelity than Dolby Digital.was fostered, in great measure, by the development
Surround Sound speaker placement: (6 speakers inof professional and semi-professional 8-track tape
total) Surround Sound speaker placement is differentrecorders - originally analog, but later manifesting in
for both music and movie content.proprietary cassette formats by Alesis and Tascam.
For music speakers are placed in a circle around theThe speaker configuration, however, is much less
listener. The center channel has 0o offset, left and righttraditional, and unlike cinematic reproduction systems,
are offset ± 30o, and thethere is no hard-and-fast 'standard'.
left/right surrounds are offset byIn fact, composers took (and to some extent still take)
±110o. Also all speakersconsiderable interest in experimenting with speaker
should be monopole, equidistant to the listener, and alllayouts. In these experiments, the goal is not limited to
delay (ms) calculations on the surround decoder shouldcreating 'realistic' playback of believably natural sonic
be turned off (0ms).environments. Rather, the goals are frequently simply
For movie surround, the front speakers should beto experience and understand the effect created by
placed at the edges of the screen, toed in to face thevariations on source and imaging.
central listening location, and the tweeters should be10.2 Channel Surround
ear height. The center speaker should be placed10.2 is the surround sound format developed by THX
behind the screen (when using projection) or over orcreator Tomlinson Holman of TMH Labs and University
under a tv, and as close to ear high as possible. Rearof Southern California (schools of Cinema/Television
channel speakers should be placed high on side walls,and Engineering). Developed along with Chris
slightly behind the listening position, and should have aKyriakakis of the USC Viterbi School of Engineering,
nomal hi quality monopolar construction.10.2 refers to the format's slogan: "Twice as good as
6.1 Channel Surround (analog matrixed: Dolby Prologic5.1". It has been touted as the audio equivalent of IMAX
IIx)- spectacle beyond what can be achieved by any
Extracts 6 audio channels and 1 LFE channel from aother format.
specially encoded stereo source:10.2 augments the LS (left surround) and RS (right
Two channels for speakers at the front - left (LF) andsurround) channels by two point surround channels that
right (RF).can more finely manipulate sound - allowing the mixer
One channel for speaker at the center - center (C).to shift sounds in a distinct
Two channels for surround speakers at the sides -360° circle around the
side left (L) and side right (R).movie watcher.
One channel for both surround speakers at the rear -The 14 discrete channels are:
mono surround channel (S).Five front speakers: Left Wide, Left, Center, Right and
One low-frequency channel using a sub-woofer (LFE).Right Wide
Describes the Dolby Prologic IIx matrixed SurroundFive surround channels: Left Surround Diffuse, Left
system. Source media is unknown.Surround Direct, Back Surround, Right Surround Diffuse
Surround Sound speaker placement: (8 speakers inand Right Surround Direct
total) Surround Sound speaker placement is differentTwo LFE channels: LFE Left, LFE Right
for both music and movie content.Two Height channels: Left Height, Right Height
For music speakers placement is unknownThe .2 of the 10.2 refers to the addition of a second
For movie surround, the front speakers should besubwoofer. The system is bass managed such that all
placed at the edges of the screen, toed in to face thethe speakers on the left side use the left sub and all
central listening location, and the tweeters should bethe speakers on the right use the right sub. The Center
ear height. The center speaker should be placedand Back Surround speaker are split among the two
behind the screen (when using projection) or over orsubs. The two subs also serve as two discrete LFE
under a tv, and as close to ear high as possible. Side(Low Frequency Effects) channels. Although low
channel speakers should be placed high on side walls,frequencies are not localizable, it was found that
to the left and right of the listening position, equidistantsplitting the bass on either side of the audience
from the front speakers and the rear speakers. Rearincreases the sense of envelopment.
channel speakers should be placed high on side walls,22.2 Channel Surround
slightly behind the listening position, and should have a22.2 is the surround sound component of Ultra High
nomal hi quality monopolar construction.Definition Video (Super Hi-vision TV with 4320
6.1 Channel Surround (digital discrete: Dolby Digital EXscanning lines), and has been developed by NHK
with a matrixed 6th channel)Science & Technical Research Laboratories. As its
Delivers 5 audio channels, 1 extracted audio channelname suggests, it uses 24 speakers. These are
and 1 LFE channel from a 6 channel source:arranged in three layers: A middle layers of ten
Two channels for speakers at the front - left (LF) andspeakers, an upper layer of nine speakers, and a
right (RF).lower layer of three speakers and two sub-woofers.
One channel for speaker at the center - center (C).The system was demonstrated at Expo 2005, Aichi,
Two channels for surround speakers at the sides -Japan and the NAB 2006 conference, Las Vegas