Sound Studio, Week 10 (October, 2007) "Surround Formats"

Format	Mixing Format	Channel/Track Layout	Brief Technology Overview	Release Format
Dolby Stereo SR (Spectral Recording)	4.0		Developed in 1986 to assist in overall dynamic range of analogue media. Used predominantly for 35mm film soundtracks. Sound information is recorded to 35mm film, which is the interpreted by a solar cell, converted as voltage information, and finally amplified.	35” film
Quadraphonic	4.0	L/R/Ls/Rs	Introduced in 1970. Quadraphonic recording used an ‘Out of Phase Stereo’ (OOPS) signal which was overlayed onto the existing stereo track, just 90° out of phase. It was then up to a specifically designed ‘matrix’ decoder to recognise this and send the out of phase signal to the surround speakers.	Vinyl, 8 track cartridges, reel to reel releases
Dolby Pro Logic II	5.1	L/C/R/Ls/Rs + 1 LFE channel	Introduced in 2000. Expands any two channel audio and extracts the information into a 5 channel full bandwidth signal. Mainly used for television broadcast, and only compatible with labelled Dolby Pro Logic home theatre systems.	Mainly TV broadcast
Dolby Digital	5.1	L/C/R/Ls/Rs + 1 LFE channel	Industry and commercial standard for most cinemas and home theatre systems. It is also a film standard, used on 35” film.	DVD, TV broadcast, game consoles, 35” film
DTS (Digital Theatre System)	5.1			DVD, 35mm film, game consoles
SDDS (Sony Dynamic Digital Sound)	8.0	L/Lc/C/Rc/R Ls/Rs + 1 LFE channel	In competitive film sound format by Sony, using 8 channels to enhance the experience of film. The format, while useful, hasn’t taken off and Sony has discontinued its support for it, however some films are still recorded with the SDDS track.	35” film
Dolby Digital Surround EX	5.1	L/C/R/Ls/Cs/Rs + 1 LFE channel	The same as Dolby Digital, however, with the addition of a matrixed centre surround channel. Most likely in competition with DTS-ES.
DTS ES (Extended Surround)	5.1/6.1		There are two versions on DTS-ES (discrete, or matrixed). ES Discrete provides 6.1 channels, with an extra centre surround channel, where as the matrixed version has 5.1 channels with an extra matrixed centre surround channel.	DVD, 35mm film, game consoles, television broadcast
IMAX	6.0	…	Six channel, “multi-digital” system to enhance the overall experience of IMAX. Utilizes an array of 44 speakers, and uncompressed audio.	70” film format only in IMAX theatres

Dolby Digital SR

Quadraphonic

Dolby Digital EX

SDDS

DTS

Dolby Digital

IMAX

Dolby Pro Logic II

Matrix Audio Recording