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Overview of Surround Formats
To get best performance from your
Dolby Surround
Dolby Pro Logic
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
Dolby Pro Logic decoding delivers a mono sig- nal with reduced
Dolby Pro Logic II decoding is used for any analog soundtrack or recording labeled “Dolby Surround” or any Dolby Digital 2.0 soundtrack. While it is specifically designed to decode Dolby Surround recordings, Dolby Pro Logic can derive surround sound from conventional
Activate Dolby Pro Logic II decoding with the Dolby PLII/3ST button described in the next section of the manual.
Dolby Digital
In 1992, an entirely new digital recording system, called Dolby Digital, was first used in the film industry. Dolby Digital is a recording/ playback system that uses compression tech- niques to store large amounts of audio data efficiently, much like the JPEG format stores large photographs in small files on a computer. 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 record up to six discrete audio channels, but can con be used for fewer. For example, a Dolby Digital
2.0recording is a
The most common use of Dolby Digital, in both the film industry and in home theater, is Dolby Digital 5.1. Instead of encoding multiple sur- round channels on a
Decoding of Dolby Digital 5.1 soundtracks is automatic. When the
5.1signal on one of its digital inputs, it acti- vates the proper processing. Keep in mind that Dolby Digital is only available from digital sources (a DVD, a LaserDisc, or a Digital TV/ Cable/SAT tuner). Also, you must connect the source with a digital cable (coax or optical) to an active digital input on the
NOTE: Many DVDs have a Dolby Digital 2.0 matrix soundtrack as the default, which should be decoded with Pro Logic II. The Dolby Digi- tal 5.1 soundtrack may have to be selected as an option from the setup menus at the be- ginning of the DVD. Look for a Dolby Digital
5.1selection under “Audio” or “Languages” or “Setup Options” when you insert the disc.
DTS 5.1
DTS® (Digital Theater Systems) is an alterna- tive digital format competing with Dolby Digital in both movie theaters and home theater markets. The basic features and functions of the DTS system are similar to those of Dolby Digital (for example, 5.1 discrete channels), however the technical details of the compres- sion and decoding processes differ somewhat and a DTS decoder is required.
Like Dolby Digital, DTS can only be used on a digital recording and, therefore, is only available 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 always 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 se- lect “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 out- put. If you here no sound the first time you attempt to play a DTS disc, you may have to go to the DVD player’s configuration menus and turn on the DTS bitstream. This is a one- time setting and need only be done once. See your DVD owners manual for details.
The
IIin that it is designed for playback of any 2- channel stereo recording, either