Dolby Pro Logic II

Deliver Five-Channel Material in One Stereo Signal to the Home

Dolby® Pro Logic® II lets users enjoy five full-range channels of surround sound from high-quality programming sources: TV broadcasts, VHS movies, CDs, satellite radio programming, video games, even FM broadcasts and cassette tapes. Now you can easily bring your movies, music, games, and TV shows into the multichannel audio world of the 21st century.

Dolby Pro Logic II can also be used to encode discrete four- or five-channel surround mixes into Left total/Right total (Lt/Rt) stereo for delivery via two-channel pipelines. Lt/Rt-encoded stereo content provides thrilling surround sound through the millions of home theater systems equipped with Dolby Pro Logic II decoding, while remaining fully compatible with stereo and mono playback. While it isn’t a replacement for the discrete 5.1-channel mix provided by Dolby Digital, it offers a compelling and convincing surround experience.

Dolby Pro Logic II is also encoded in games and broadcast or satellite radio programming to achieve specific directional effects and provide five-channel playback when decoded through consumer systems equipped with Dolby Pro Logic II.

Where You’ll Find Dolby Pro Logic II

Dolby Pro Logic II is incorporated into advanced home theater receivers, car audio systems, game consoles, and an increasing number of PCs. It is fully compatible with Dolby Surround encoding technology (also referred to as Dolby Pro Logic), and can properly decode the thousands of titles encoded in Dolby Surround available today.

Features 

  • Delivers five full-range, independent channels of surround sound from two-channel sources, including TV broadcasts, VHS tapes, CDs, cassettes, MP3 files, FM broadcasts, and video games.
  • Movie and music modes allow you to adjust the sound according to the content.
  • Music mode offers three consumer-adjustable features to enable you to fine-tune the sound.
  • Further enhances surround sound playback for Dolby Headphone and Dolby Virtual Speaker technologies.

Benefits 

  • Uses existing stereo infrastructure to deliver multichannel surround programming.
  • Transforms high-quality stereo content into a natural and realistic surround sound listening experience.
  • Enhances your listening experience without sounding processed or artificial.
  • Applies Dolby expertise in matrix surround sound technology to produce a natural listening experience.

Technical Summary

Dolby Pro Logic II enables broadcasters and content creators to carry convincing, realistic surround sound on their stereo-only services. By employing the latest matrix-steering techniques and two rear channels, the system gives realistic surround sound when the transmission medium is limited to two channels. Dolby Pro Logic II programs are matrix-encoded onto two tracks during production, treated as stereo throughout the broadcast chain, and finally decoded back into surround sound by the home cinema, television, or game console.

With the introduction of discrete 5.1-channel mixing, Dolby Laboratories developed the Dolby Pro Logic II matrix encoding system to allow this signal to be carried on a two-channel pipeline. Dolby Pro Logic II technology allows content providers to deliver exceptional soundtracks to consumers regardless of the capabilities of their home theater systems because it was designed to work with all two-channel audio sources. It is also completely backward compatible with the original Dolby Pro Logic decoder.

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