Dolby Pro Logic takes its information from a two-track-stereo format. When a movie is recorded in Dolby surround, the Stereo soundtrack is recorded on the tape. Certain sounds (the surround-channel information) are encoded. Inside the Dolby Pro Logic receiver, the Pro Logic circuitry decodes the surround information and sends it to the rear channels. The center channel is derived by removing what is equal or nearly equal in the left and right channels and sending it to the center.

Dolby Digital AC-3 is a technology developed by Dolby Laboratories that allows us to store much more CD-quality audio in much less space than traditional CD-audio. Dolby Digital also allows us to present soundtracks in the home that offer a complete surround sound experience, just like at the movie theatre, with left, centre, and right channels, stereo surround channels and a subwoofer.

Dolby Digital (AC-3) is a digital sound compression technique developed by the Dolby Laboratories Licensing Corporation. Supporting 5.1-channel surround sound, as well as stereo (2-channel) sound, this technique enables a large quantity of sound data to be efficiently recorded on a disc. However, nowadays, the understanding has become to be Dolby Digital (AC-3) = Dolby Surround = Dolby Digital 5.1.

Dish Network currently only provides Dolby Digital soundtracks on their ‘home theater’ Pay-Per-View channels 512-513 on the 119 satellite and PPV channels 520-525 on the 110 satellite. You can look for the “DD” symbol in the Electronic Program Guide (EPG) to see if the movie is broadcasted in Dolby Digital. These channels also show some movies in their original letterbox format. DISH Network will expand their DD offerings through time.

Both methods are what's known as lossy data compression schemes where some information that is masked by more prominent data is thrown away. This is done in order to fit a lot of data through a small data pipe. Dolby Digital (formerly called AC-3) takes 6 channels of 48kHz/24 bit information and compresses it at about an 11 to 1 ratio to an a maximum bit rate of 640kbps, although 384 is the average data rate used. DTS compresses at about a 3 to 1 ratio at an average data rate of 1.4Mbps.

Both are decoding systems for home theater sound. Dolby Digital is the successor to Dolby Pro-Logic. Pro-Logic is actually four channels of sound that is reproduced through five speakers. The four channels are: left, center, right and the left/right surround channels. In Pro-Logic mode the rear speakers are in mono. Pro-Logic is typically found on an analog source Ex: VCR tapes.

Most DVD-Video discs contain Dolby Digital soundtracks. However, it's not required. Some discs, especially those containing only audio, have PCM tracks. It's also possible for a 625/50 (PAL) disc to contain only MPEG audio, but so far MPEG audio is not widely used. Don't assume that the "Dolby Digital" label is a guarantee of 5.1 channels. A Dolby Digital soundtrack can be mono, dual mono, stereo, Dolby Surround stereo, etc.

These are all digital encoding techniques to allow a multichannel signal to be delivered to the consumer. The main difference between them is the number of channel and how the signal is decoded. While Dolby Surround and Pro Logic are closely related (with the main difference being the fact that Surround uses a passive decoder while Pro Logic uses an active one), Dolby Digital is a completely different, more sophisticated technique and not compatible with the others.

We are able to offer some movies with Dolby 5.1. If your audio visual equipment supports and is set up for Dolby Digital, you will be able to hear those movies in 5.1 surround sound.

Dolby Pro Logic is a matrix decoder that decodes the four channels of surround sound that have been encoded onto the stereo soundtracks of Dolby Surround program material such as VHS movies and TV shows. Dolby Surround (or Dolby matrix!) is a matrix encoding process that in essence "folds" Left, Center, Right, and Surround channels onto stereo soundtracks. A Pro Logic decoder "unfolds" the four channels on playback (without a Pro Logic decoder, the encoded program plays in regular stereo).

Yes, DVD-V200K does have a built-in decoder with Dolby Digital (Surround) (AC-3) processing; however, the output is only 2-channel stereo. No, from the modem day definition/understanding of a so-called built-in AC-3 decoder. Regardless, you can attach the DVD-V200K to a Dolby Digital-ready (i.e., 5.1-ready) A/V receiver/processor/amplifier to enjoy the benefits of 5.1 channel surround sound audio.

One of the technical specifications of DVD states that every disc must use at least one PCM or Dolby Digital soundtrack to ensure the medium's high quality throughout all its publications. Dolby Digital is a sound format that allows to have up to six different channels of sound, making for a full surround experience of your movies. One of the most common used versions of Dolby Digital is its 5.1 channel implementation.

Dolby Digital is 16 bits of PCM Linear Tracking that is compressed. DTS is 20 bits of Master quality audio that is not compressed. Dolby Digital and DTS are similar in that they are both digital lossy audio coding technologies, which means they use "perceptual" data reduction techniques that are based on the characteristics of human hearing to mask the process, thereby preserving high fidelity sound. This is necessary in order to fit the typical 5.

Dolby® Digital technology is an advanced form of digital audio coding that makes it possible to store and transmit high-quality digital sound far more efficiently than was previously possible. First used in movie theaters in 1992, Dolby Digital technology is the result of decades spent by Dolby Laboratories developing signal-processing systems that exploit the characteristics of human hearing.

Dolby Digital programs can deliver surround sound with up to five discrete full-range channels: Left, Center, Right, Left Surround, Right Surround-plus a sixth channel for powerful low-frequency effects. As it needs only about one-tenth the bandwidth of the others, the LFE channel is referred to as a ".1" channel (and sometimes erroneously as the "subwoofer" channel).

Discs in countries such as the US that use the NTSC broadcast TV standard must provide at least one soundtrack in either of two formats: Dolby Digital or PCM (the format used on CDs). In countries using the PAL TV standard, including much of Europe, the discs must include at least one soundtrack in any one of three formats: Dolby Digital, PCM, or MPEG. Due to these requirements and the options they permit, not all discs may have Dolby Digital soundtracks.

The technology behind 5.1-channel Dolby Digital provides two surround channels, instead of the one from Dolby Surround, for more precise localization of sounds and a more convincing, realistic ambience. Also, Dolby Digital's surround channels cover the entire audible range (20 Hz-20,000 Hz), whereas the range of Dolby Surround's single surround channel is limited (100 Hz-7,000 Hz). The increased range of Dolby Digital further heightens realism and gives sound mixers more creative freedom.

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AAC is a state-of-the-art audio compression algorithm that provides compression superior to that provided by older algorithms such as AC-3. AAC and AC-3 are both transform coders, but AAC uses a filterbank with a finer frequency resolution that enables superior signal compression.