Digital Versatile Disc

DVD Video Players

Your current home theater setup largely determines the features and price level you'll be looking for. If your system is modest, then a budget player (under $300) should do fine. Picture quality differs dramatically from one player at the low-end to a highend player.  More expensive players (from $500 to $1,000) will provide a better picture quality, smoother fast and slow picture scanning (particularly during reverse scanning), and various fun features - picture zoom, for example. These players will integrate nicely with average to good home theaters. Top-price players (over $1,000) provide uncompromised video and audio quality and a full set of features.  In addition, their typically superior construction quality and styling can add to your pride of ownership. These models are appropriate for deluxe home theaters where cost is no object.
Dolby Digital Decoding: Onboard or Outboard?  One of the most exciting aspects of home theater and DVD is surround sound.  Many discs contain 5.1-channel Dolby Digital (DD) soundtracks which are five discrete audio channels
The Basics  DVD-Video players deliver composite-video and S-video signals playable on a conventional TV.  Video features such as fast-scan, freeze-frame, and stop-frame motion (a kind of incremental slow-mo) can be found on most players. All have a built-in menu system that lets you set up and control the player, and let you navigate the menus on DVDs that provide access to the contents, including special features like storyboards and directors' comments.  DVD players put out analog stereo signals as well as a digital audio bitstream from CDs and DVDs. The digital signal can carry Dolby Digital surround sound or standard PCM stereo, depending on how the disc is encoded or which audio track is selected. Most newer players can also pass a DTS-encoded digital signal from those few discs with DTS soundtracks. To play it safe, make sure your player is DTS-compatible so that if DTS's popularity takes off, you'll at least have the option of passing the signal to an external processor or receiver with a DTS decoder. Receivers increasingly offer this because they contain digital signal processing (DSP) chips that can handle both Dolby Digital and DTS decoding - the processor simply senses the signal format and switches in the appropriate decoding software. DTS compatibility isn't absolutely necessary, however, because DTS discs must also carry PCM or Dolby Digital soundtracks for playback in stereo or Dolby Surround.

plus a dedicated low-frequency-effects (LFE) or ".1" channel for deep bass. To hear this surround sound, you'll need a DD decoder, which can reside either inside the DVD player or in your A/V receiver (or surround processor).
In general, it's better if the decoder is in the receiver. There it is accessible to other components that output signals that need decoding, such as a satellite receiver, and it reduces the wiring between the player and the receiver: the undecoded DD signal requires only one cable to carry it, whereas a decoded 5.1-channel analog signal requires six. Also, receivers are usually better equipped than a DVD player with onboard decoding to handle the bass-only low-frequency-effects (or ".1") channel.  A DD decoder in the player really makes sense only if your receiver lacks one.

And in the worst case, you can get along without Dolby Digital at all. The analog stereo signal in most DVDs is Dolby Surround-encoded, and any A/V receiver will be able to decode that into surround sound.
96/24 Compatibility.  When people think of DVD-Video, they rightly think of its awesome picture quality. But DVD also offers awesome sound quality. In particular, it accommodates stereo sound sampled at 96 kHz and with a resolution of 24 bits - far above the CD standard in terms of frequency response and dynamic range. A few record labels (most notably Chesky) are offering music-only DVD-Video discs with 96/24 specs. Some players won't play these discs. Some do play them, but at lower fidelity, downsampling the signal from 96 kHz to a lower sampling rate such as 48 kHz, or reducing the resolution to 20 bits or less, or both. Finally, some players play the full signal. Yet again, read the fine print!
Outputs.  Some folks buy a component based on its flashing-light count. Smarter folks look at the back panel, because the number of inputs and outputs largely determines how useful the component is and how "future-proof" it might be. Most DVD players don't have any inputs, but look carefully at the outputs. As mentioned previously, all models have both composite-video and S-video outputs. More and more DVD players also have a component-video output, the highest-quality video signal. Even if your current TV doesn't accept this, your next TV might.
When it comes to digital audio outputs, make sure the player at least has the same kind of output as your receiver's digital input. Some have only a coaxial or only an optical output, others have both, and still others have two of each. Of course, players with built-in Dolby Digital decoders also have a set of six analog outputs.
Special Features.  All DVD players let you play discs straight through, select among their contents, and amuse your friends with fast and slow playback. A few players add other useful features. For example, top-end players provide comprehensive video controls to tweak the picture and to reduce video noise. Some players automatically select the 5.1-channel soundtracks (if available), while other players require manual selection. If you have a big laserdisc collection, combi-players play both laserdiscs and DVDs as well as CDs.  Theta and Pioneer seem to be the leaders in the combi-player arena.

Surround History

    Dolby is one of the best-known names on the planet. For starters, it appears on about a zillion cassettes. And Dolby has long been a benchmark for high-quality sound in movie theaters. Dolby Digital (DD), with its five discrete audio channels plus a dedicated low-frequency-effects (LFE) or ".1" channel for deep bass, hit the big screen in 1992 with the action/adventure flick Batman Returns. More than 9,000 movie theaters in North America are now equipped for Dolby Digital playback, which delivers more realistic and engaging sound than the Dolby Stereo system that was introduced to theaters in 1976 (it wasn't until the following year that Star Wars really turned moviegoers on to surround sound). On the domestic scene, most DVDs have Dolby Digital 5.1-channel soundtracks, and literally millions of decoders - mostly built into A/V receivers - are in consumers' hands.
A year after Dolby Digital made its debut, Digital Theater Systems (DTS) launched its rival format with the

release of Jurassic Park. Also a 5.1-channel system, DTS is conceptually the same as Dolby Digital yet incompatible with it. It has made impressive inroads against Dolby's lock on cinema sound. Thanks to backing by Hollywood moguls like Steven Spielberg, DTS playback equipment is installed in close to 9,000 movie theaters in North America. On the home side, DTS decoders are appearing in more and more components, including a number of A/V receivers, and the first batch of DTS-encoded DVDs became available sometime ago.  When the consumer-electronics industry's DVD Working Group sought the best audio coding technology for the new format back in 1995, Dolby Labs was fast out of the blocks. Dolby argued that its name recognition, its

familiarity with the movie industry, and the choice of its system for audio coding in the new digital TV (DTV) standard made it a natural for DVD as well. The DVD group agreed, and Dolby Digital was selected as one of the two "mandatory" soundtrack formats for DVDs released in the U.S., meaning that at least one of them has to be on each disc. A two-channel PCM soundtrack like those found on CDs is the other mandatory format.
Late to the party, DTS argued that its coding method sounds better than Dolby Digital because it uses a higher bit rate and therefore that the DVD standard should be changed. The DVD Working Group was not moved, and DTS was relegated to the dreaded "optional" status, meaning that any DVD carrying a DTS soundtrack must also have either a PCM or a DD soundtrack. (Note, however, that a DD soundtrack is not necessarily 5.1-channel - it can range from mono to 5.1 channels, and can also be a two-channel stereo track carrying Dolby Surround information.) Because the decision to add DTS as an optional format was made after the DVD format was officially launched, first-generation DVD players are incompatible with DTS.