What is 5.1 channel surround sound?
"5.1: This is the most commonly used surround sound format in DVDs. This audio format supports five separate main channels (left,center,right,rear left, rear right) fill full frequency response and one subwoofer channel (limited typically to 120 Hz and below). This audio format is supported for example with Dolby Digital and DTS."
"6.1: The 6.1 channel system is like 5.1 channel system but adds rear center channel. If the rear center is not present in the source (as you noted most DVD's only have 5.1) the receiver will take part of the left rear and part of the right rear and create the center rear channel. There are some DVDs with 6.1 encodings (Dolby Digital EX, DTS-ES). DTS-ES is a discrete 6.1 channel format (i.e. there is 6.1 channels of audio that is mixed specifically like that) Dolby Digital EX is a matrixed 6.1 channel format (i.e. there is 5.1 channels of discrete audio and the extra channel, the rear centre, is matrixed from the rear left and rear right channels)"
"In 7.1 set-ups the extra 2 channels to 5.1 system. Those extra speakers are are usually side speakers (placed somewhere between the front and the rear speakers, usually more towards the front speakers). The 7.1 mix is matrixed from 5.1/6.1 mixes. This matrix is usually a format made up by the manufacturer of the decoder."
"The digital sound format known as 5.1 (representing typically 6 channels of sound) was developed for movie presentation in theatre settings. Because home environments are different than movie theatres, the same THX audio standards that ensured accurate playback in theatres have been adapted for viewing movies in DVD, VHS, satellite and broadcast formats at home."
"Incorporating a variety of digital encoding technologies like Dolby Digital, DTS and PCM, THX Certified Home Theatre products offer the most consistently accurate, trouble-free reproduction of sound."
Who is Dolby?
"Dolby Digital 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, it is the result of decades spent by Dolby Laboratories developing signal-processing systems that exploit the characteristics of human hearing."
"Dolby Laboratories develops audio signal processing systems and manufactures professional equipment to implement these technologies in the motion picture, broadcasting, and music recording industries. Dolby also licenses these technologies for use in the consumer electronics industry. Providing the best possible audio for any entertainment environment, including music, movies, television and multimedia, is Dolby's primary commitment."
"Today, Dolby Laboratories continues to pursue genuine, long-term improvements in sound quality. Dolby analog and digital developments are incorporated in both professional products that the company itself manufactures, and under license in professional and consumer products from other manufacturers."
"Dolby technologies are used by sound professionals everywhere, are thrilling audiences in tens of thousands of cinemas every day, and are featured in consumer media that includes audio cassettes, home theater systems, television and satellite broadcasts, and video and computer games."
Who is DTS?
"Dedicated to delivering the 'Ultimate Entertainment Experience,' DTS has created a media-delivery format that makes audio tracks sound more dynamic, more realistic and more closely matching the original than other digitally encoded soundtracks and consumer media. Coupled with the multi-dimensional playback benefit of surround sound technology, DTS audio quality dramatically improves and enhances content. Today, DTS continues to develop and expand its technology and services in current markets and beyond, including the existing opportunities offered in the broadcast arena and broadband entertainment."
"For home theatre and music playback in the home, DTS provides high quality 5.1-channel surround sound with many extras not offered by other consumer formats. As well as handling DTS-branded releases from a growing number of music labels and consumer software producers, DTS provides enhanced 6.1 matrix and DTS 6.1 discrete decoding that envelopes the listener in sound. DTS technology is featured in a wide cross section of receiver/pre-amplifiers, DVD players and add-on components from leading consumer audio vendors."
"Dolby uses more compression than DTS. Dolby Digital sounds good, but DTS delivers all of the clarity and dynamic range contained within the original master soundtrack."
Our purpose is to understand the artist's vision and intention, and provide them with the creative tools to unlock the power and emotion of their stories.
This following is based on tests that were done by both Dolby and DTS in trying to prove which one is better:
Dolby Evaluates DTS
"Dolby has been selling encoders and decoders ever since Dolby Digital was adopted by consumer formats, to support the creation of content. DTS has issued various reports and statements reflecting their tests and opinions of Dolby coding going back to at least 1995. They have also issued a CD intended to compare the audio quality of DTS and Dolby coding to the source signals. Some of their published findings showed obviously flawed measurement practices. Dolby issued a detailed reply with correct data in October, 1995."
"While none of these tests prove that DTS and Dolby Digital sound identical to each other, or to the source master, they do show that there are many reasons, some more subtle than others, why there ought to be audible differences between DTS and Dolby Digital versions of the 'same' soundtrack. That consumers can hear these differences should not come as any surprise. That all such differences can be attributed solely to the coding technologies should not come as an automatic conclusion."
"Dolby Laboratories has recently published a brief paper describing their evaluation of the DTS CD/DVD encoder/decoder set. The paper, as might be expected, asserts the superiority of Dolby Digital over the DTS Digital Surround system. Such a finding from a principal competitor is suspect on its face. It appears that the paper is being appropriately discounted by informed observers, making a response from DTS perhaps superfluous; nevertheless, there are a number of points that need correction."
"Dolby urges that studio professionals perform their own comparative tests. DTS also urges such comparisons – preferably without the interference of interested parties. The pertinent comparison is not DTS versus Dolby Digital, but either coder versus the unencoded original master. DTS would prefer to work in parallel with Dolby in expanding the multichannel market, rather than continue with charges and refutations. In the end, Dolby Digital is a useful technology where space or bandwidth is sufficiently restricted. DTS provides a different path when concerns for artistic and acoustic integrity are paramount."
Who is THX?
"THX Ltd. is the founder of quality assurance programs for superior cinema presentation and the leading provider of product certification and venue design for the entertainment and consumer electronics industries. It was established in 1983 by George Lucas to ensure that the entertainment consumer experienced films as the director intended. For nearly two decades THX has played an integral role in the evolution of audio and video standards, defining optimal performance for the world's premiere hardware manufacturers and recording and presentation venue designers. Today, THX Certification assures the finest sound and picture quality for cinemas, mixing studios, home theatres, DVDs, multimedia products, and luxury automotive vehicles."
What is THX certification?
"THX Certified Home Theatre products deliver cinema-quality picture and sound to home environments. Through optimized audio-visual technology and speaker placement, you get a movie experience at home that's as faithful as possible to the director's design."
"Today's big special-effects movies can have hundreds of separate sound elements in the soundtrack. Dialogue, sound effects and music are all independently recorded and then mixed down to a six- (5.1) or four-channel soundtrack for cinema release. But when the cinema-designed sound is translated to home theatre, significant sonic quality is lost in the translation."
"Is THX Home Theatre compatible with Dolby Digital and DTS? Absolutely! The goal of THX Home Theatre is to accurately recreate the experience of the film mixing theatre. All mixing theatres are capable of creating both 4 and 5.1 channel mixes. The acoustics, equalization curves, and loudspeaker arrays used in a mixing theatre remain the same for a digital 5.1-channel soundtrack as they do for a 4-channel Dolby Surround soundtrack. THX Home Theatre technologies are needed to reproduce these movie soundtracks accurately."
What is the DB System?
"The DB System is nothing more than just another layer with speakers and amplifiers added to an existing system to enhance the sound to make it more realistic. You may know that, a 3D image of a sound can be "created" only with two speakers. Now try to imagine all this multiplied by all the numerous speakers in a DB System."
THX claims to "ensure that the entertainment consumer experienced films as the director intended." This is where Dolby and DTS have come a long way to make it possible through developing multichannel format technologies to electronically deliver the digital sound on DVD to the consumer, defining what we know today as surround sound. But the reproduction thru speakers and amplifiers is lacking.
This is where the DB system comes in (1994), with the goal of 'making the sound part of the picture' by actually making also the right hardware to reproduce "the well-defined sound where the energy and emotions of music and film could be felt by the audience with the same intensity intended by their creators."