Joonas Tuominen SURROUND SOUND

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 channelsAudible channelsSpeakers Mono 111 Stereo 222 Pro Logic (DD 2.0) 244 – 5 Pro Logic II 255 Dolby Digital 5.1 (DD 5.1) 65,16 DTS 666 Dolby Digital EX ,17 – 8 DTS-ES – 8 DTS-ES Discrete 777 – 8

POSITIONING Two speakers positioned to the front-left and front-right of the listener, form about a 30° angle

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! volume-without-pissing-your-neighbours-off volume-without-pissing-your-neighbours-off-101

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