SURROUND SOUND
Joonas Tuominen
WHAT DOES ”SURROUND SOUND” MEAN?
• A technique for enriching the sound reproduction quality of an
audio source with additional audio channels from speakers that
surround the listener
• Aims to produce a sound field with a 360° radius in the
horizontal plane
HISTORY
• First documented use in 1940 for the Disney film Fantasia
• The first system was called “Fantasound”, three channels and
speakers
• Only for experimental use, was excluded in later showings
• Returned in the 1950s as composers started experimenting with
surround sound (Karlheinz Stockhausen, Edgar Varese)
HISTORY
• 1978: Max Bell’s ”Split surround” for Dolby laboratories
• Tested with ”Superman” and perfected with ”Apocalypse Now”
• The 5.1 in 1987 at the famous French Cabaret Moulin Rouge
THE BASICS
• A surround sound system consists of program sources (a
television etc.), the amplification system, speakers and
mounting accessories (cables etc.)
• Can be created with a minimum setup of two speakers
• Most common setup is the 5.1-system
NOTATION
• x.x notation style
• The first digit reflects the number of full range channels
• The second digit reflects the limited range of the LFE channel
• E.g. ”2.0”, ”5.1”, ”7.2”
TECHNOLOGIES
• Most important ones by two companies, Dolby and DTS
Stored channels
Audible channels
Speakers
Mono
1
1
1
Stereo
2
2
2
Pro Logic (DD 2.0)
2
4
4–5
Pro Logic II
2
5
5
Dolby Digital 5.1 (DD 5.1)
6
5,1
6
DTS
6
6
6
Dolby Digital EX 6.1
6
6,1
7–8
DTS-ES 6.1
6
7
7–8
POSITIONING
• Two speakers positioned to the front-left and front-right of the
listener, form about a 30° angle
POSITIONING
POSITIONING
• 4.0-system: Two ways
• three speakers in front and one behind
• two speakers in front and two at the back
• A five speaker setup: three in front, two at the back, 110° angle
POSITIONING
BASS MANAGEMENT AND LFE
• Surround systems may make use of
bass management = Not mandatory
• Means the directing of low frequency
sounds to certain speakers
• LFE = Low Frequency Effects (channel)
• A separate channel to carry extremely
low “sub bass” sounds
BASS MANAGEMENT AND LFE
• A subwoofer can be added to any setups
• Enables better production of low frequency sounds.
• Positioning: Anywhere around the other speakers, human
hearing cannot distinguish the direction
FUTURE STUFF
• 22.2, surround sound for Ultra High Definition Television,
developed by NHK Science & Technical Research Laboratories.
• 24 speakers arranged in three layers: A middle layer of ten
speakers, an upper layer of nine speakers, and a lower layer of
three speakers and two sub-woofers.
SOMETHING COOL
• Psychoacoustics!
• http://www.vice.com/en_uk/read/guy-invented-system-boostvolume-without-pissing-your-neighbours-off-101
THANK YOU!