What is Dolby's effect?

Answer 1

Are you referring to the Dolby noise reduction system? It's process to make recordings more tolerant of the noise inherent in the recording process. This is accomplished by boosting the high frequencies in the sound recording to mask out the high frequency noise in the recording medium. On playback, the high frequencies are attenuated, along with the noise, resulting in a psychoacoustically "noise-free" sound:
http://en.wikipedia.org/wiki/Dolby_noise_reduction_system

Answer 2

Noise reduction by minimizing the inherent tape hiss in a recording. Kind of obsolete these days of direct to digital recording techniques.
It seemed to gain quite a following, but I never really thought it did much but crop the high end off the sound spectrum. But, that was just my opinion - the sound just seemed more natural and "real" when the Dolby function was disabled.

Answer 3

If u r talking about bolby noise used in cinema halls, its used to give the listener the feeling of Doppler's effect.

Answer 4

Dolby Digital and DTS are six-channel digital surround sound systems and are currently the standard in major motion pictures, music, and digital television. They both use the 5.1 speaker format The format consists of three speakers across the front and two speakers in the rear. The .1 is a sixth channel called an LFE that is sent to a subwoofer.

Dolby Digital uses the AC-3 file format, which any Dolby Digital Decoder can decoder to produce 5.1 audio. Dolby Digital is the technical name for Dolby's multi-channel digital sound coding technique, more commonly referred to as Dolby 5.1. A six-channel sound coding process (one channel each for front, left, center, right surround, left surround and a sub-woofer) originally created by Dolby for theaters, AC-3 was subsequently adapted for home use and is now steadily becoming the most common sound format for DVD.

DTS is an encode/decode process that delivers 5.1 channels of "master quality" audio on CD, CD-R, and DVD. Each DTS encoded disc represents a sonic "clone" of the original film soundtrack.

DTS is very similar to AC-3 in it's intended uses.

DTS can also be put onto a CD-R and played back on any CD Player with a digital (S/PDIF or Toslink) digital output which is connected to a DTS receiver (decoder+amplifier). DTS has a superior sound than that of Dolby Digital (AC-3). For playing back Music in 5.1 surround DTS should be used. 5dot1.com will be using Dolby Digital for downloading song demos. We will be using DTS on any multi-channel CDs.

The difference between Dolby Digital (AC-3) and DTS is:
(We don't want to start any format wars etc... Both systems are great)

DTS seems to provide a deeper and tighter low frequency presence
DTS allows the sound to breath - transparency
AC-3 seems to leave the impression that something is missing from the mix.
At lower bit-rates AC-3 starts to sound like MP3's encoded at 96kbps (artifacts)
DTS is more three dimensional. The sound actually moved forward from the individual speakers to sound more full. This fullness was most apparent with the music. Instead of simply coming from the speakers, the DTS filled the front soundstage not only side to side, but with more depth as well. Bass reproduction was also more defined in the DTS version, leaving the DD edition sounding muddy.

Objective Findings:

DTS has a 3:1 compression ratio versus Dolby Digital's 12:1. This gives DTS a lot more data to deal with and they do indeed make excellent use of it. DTS sound is noticeably more open, cleaner, and more spacious and natural than Dolby Digital.

When comparing the two technologies, most consumers refer to 3 sonic advantages for DTS:

Subtle Nuances - Every individual sound effect is crystal clear, adding to the sonic realism of the soundtrack.

Dynamic Range - The loudest "bangs" have more depth, and the quietest passages are "noise-free".

Channel Separation - All 5.1 channels operate at full potential without sonic "bleeding" or "collapsing".

Does the high data rate used for DTS 5.1 soundtracks result in lower video quality or fewer "extras" on a DVD?

No. DTS takes up more space than a Dolby Digital soundtrack -- which is one reason it has higher fidelity - and (at 1.5 Mbit/s) exactly the same space as a PCM stereo soundtrack. This leaves plenty of room for high quality video, a commentary track, trailers and "making of" documentaries, etc. all on a single disc!

However, some DTS-encoded DVDs may be released with fewer (or different) extras than the non-DTS versions. This is simply the decision of the producer of the disc, and not usually the result of space limitations.

Please note: The Dances with Wolves 2-disc package is an exception that represents a special "collector's" version with the absolute highest video and audio data rates possible.

Why do some DTS tracks sound louder than the Dolby Digital version?

DTS soundtracks are delivered to the end user at exactly the overall level of the master, to preserve the full quality of the original.

Dolby Digital incorporates dialog normalization, which alters the decoded level of the soundtrack. The typical setting reduces level by 4 dB; other reduction levels are possible. In most decoders, this leads to a reduction in signal-to-noise and dynamic range.

Dolby Digital also provides a "stereo downmixing" feature as a substitute for a dedicated stereo mix. However, many production engineers have admitted that they often have to modify the original 5.1 mixes in order to attain acceptable stereo downmixes. Therefore, the 5.1 mix on many Dolby Digital DVDs may differ from the original master.

Will my DVD player play DTS DVD titles?

All DTS DVDs play in 2-channel (stereo) on all DVD players within the respective DVD regions. To experience 5.1-channel DTS Digital Surround, you need a DVD player with the DTS "Digital Out" logo, plus a surround processor (pre-amp or receiver) with a built-in DTS decoding circuit.

Please note: Most DVD players require a one-time set-up command to "activate" the DTS Digital Out playback feature. Your owner's manual explains this feature in detail.

Why do some DTS DVD's have fewer "extras", yet cost more than other versions?

DTS currently does not release, author, or manufacture DVDs or laserdiscs. These discs are authored, replicated, and sold by the studios and/or distributors who hold the rights to market them under the various video formats.

These studios and/or distributors use the DTS encoding technology under license, and DTS has no control over any decision relating to the choice of titles, per-disc pricing, video/audio extras, video bit rates, or anything else relating to DVD authoring. Please refer all specific questions or requests of this nature, directly to the content providers.

Which DTS titles will become available and where can I buy them?

The DTS website (www.dtsonline.com) is continually updated with the latest software announcements. All indications point to over 100 titles in the market before the end of 1999.

Many audio/video hardware retailers, who specialize in 5.1 audio systems, display and sell these DTS discs. Over time, the mainstream video stores and record retailers will also maintain a DTS software section. At the same time, many of the DVD Internet "stores" already have DTS titles in stock, and can easily ship them directly to your door.

Is the future of DTS solid enough to justify my investment?

After 5 years in business, DTS is currently stronger than it has ever been. and the progress to-date is only a fraction of the forecasted growth for the next 5 years.

The Cinema Division of DTS (Digital Theater Systems) began in 1993, with a unique patented system for delivering high-resolution multi-channel audio for motion pictures. Today, DTS playback equipment is installed in over 16,000 theaters around the world. and is the preferred delivery format for many top industry producers and sound engineers.

The DTS Consumer Products rollout began just three years ago, and already, DTS Digital Surround is installed in more than 50 different surround processors and decoders. And DTS-encoded soundtracks are already available on hundreds of CD, LD, and now DVD titles.

The combined progress of these two divisions represents one of the fastest market penetration stories in the history of the entertainment industry.

What do you need to playback DVD on the PC?

To enjoy DVD on the PC, the most important component you'll need is the PC DVD-ROM drive. You will also need a DVD decoder, which can come in the form of software, like Intervideo's WinDVD 2000 or CyberLink's PowerDVD 2.55. Hardware DVD decoders are also available, such as Creative's PC-DVD Encore Dxr3 .

If you choose the software option, it is important to note that it takes a lot of processing power to decode DVD Video. Therefore, you will need a very fast CPU (Pentium 300 MHz and above) to complete the task. Even then, your PC's resources will be tied up with the decoding of video and audio and you will not be able to run any other software simultaneously. This means that any game that uses Dolby Digital may suffer from performance degradation.

Creative's PC-DVD Encore series does the decoding with a separate, dedicated hardware decoder; much less CPU power is needed. The picture and sound quality is also greatly improved.

Of course, a movie wouldn't be very interesting without sound, so you will need a sound card and speakers as well to complete your basic set-up. In this case, the decoder will extract the sound from the DVD, downmix it into stereo and pass it to the sound card. Usually, the decoder will also send the compressed Dolby Digital signal out its own SPDIF output (in the case of hardware decoders), or via the sound card's SPDIF output in the case of some software decoders.

Sound Blaster Live! and Dolby Digital
To get Dolby Digital surround sound in 5.1 channels on your PC, a Dolby Digital decoder is normally required. The Dolby Digital signal from the DVD decoder card is decompressed into 5.1 channels and then sent to the various speakers, giving you the full surround sound.