Overview of
Surround Formats
To get the best performance from your
NOTE: The
Dolby Surround
Dolby Pro Logic II
The most widely available surround sound format for consumer audio/video is Dolby Surround®, available on nearly all commer- cial VHS tapes, many television broadcasts, and most DVDs. Dolby Surround is the con- sumer version of the analog Dolby Stereo system first introduced in the film industry in 1972. It is a
The original Dolby Pro Logic decoder delivered
amono signal with reduced
Dolby Pro Logic II decoding should be used for any analog recording labeled “Dolby Sur- round” or any Dolby Digital 2.0 soundtrack. Dolby Pro Logic II does a superb job deriving surround sound from conventional
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Dolby Digital
In 1992, a digital recording system, called Dolby Digital, was first used in the film indus- try. Dolby Digital is a recording/playback system that uses compression techniques to store large amounts of audio data efficiently, much like the JPEG format stores large pho- tographs in small files on a computer. Be- cause it is capable of performance beyond that of audio CDs and can tailor its output for a wide ranges of system configurations, Dolby Digital is the standard audio format for DVDs and for digital television broadcasting in the United States.
The Dolby Digital system can be used to re- cord up to six discrete audio channels, but can also be used for fewer. For example, a Dolby Digital 2.0 soundtrack is a digital 2- channel recording of a matrix encoded Dol- by Surround soundtrack.. To play a Dolby Digital 2.0 recording, use Dolby Pro Logic II decoding as previously described.
The most common use of Dolby Digital in newer films, in both the film industry and in home theater, is Dolby Digital 5.1. Instead of encoding multiple surround channels on
a
Decoding of Dolby Digital 5.1 soundtracks is automatic. When the
English
NOTE: Many DVDs have a Dolby Digital 2.0 matrix soundtrack as the default, which should be decoded with Pro Logic II. The Dolby Digital
5.1soundtrack may have to be selected as an option from the setup menus at the beginning of the DVD. Look for a Dolby Digital 5.1 selec- tion under “Audio” or “Languages” or “Setup Options” when you insert the disc.
DTS 5.1
DTS 96/24
DTS® (Digital Theater Systems) is an alterna- tive digital format competing with Dolby Digi- tal in both movie theaters and home theater markets. The basic functions of the DTS sys- tem are similar to those of Dolby Digital (for example, 5.1 discrete channels), however the technical details of the compression and decoding processes differ somewhat and a DTS decoder is required.
A recent extension of the DTS encoding sys- tem is DTS 96/24. These recordings provide the performance of a 96kHz sampling rate while still using actual 48kHz sampling rate of standard DTS discs.
Like Dolby Digital, DTS can only be used on a digital recording and, therefore, is only avail- able for home use on LaserDiscs, DVDs, or other digital formats. To use the
As with Dolby Digital 5.1, detection and proper decoding of DTS 5.1 signals is automatic.
NOTE: DVDs with a DTS soundtrack almost al- ways have it configured as an option to the standard matrix Dolby Surround format. To use DTS, you may have to go to the setup menus at the beginning of the DVD and select “DTS 5.1” instead of “Dolby Surround” or “Dolby Digital 5.1”. In addition, many DVD players have the DTS digital bitstream turned off by default and cannot output a DTS soundtrack (even if selected on the disc’s menu) until you activate the player’s DTS output. If you hear no sound the first time you attempt to play a DTS disc, go to the DVD player’s configura- tion menus and turn on the DTS bitstream. This is a