Advanced Digital Audio Codecs

DTS standards
DTS (Digital Theater Sound) is a digital sound coding standard created by Universal. Compared with the Dolby Digital standard, DTS uses four times less compression and digitises sound at 20 bits instead of 16. Therefore, DTS's sound quality is theoretically higher, at the cost of a higher bit rate. To be able to play DTS-encoded media, you need a certified DTS decoder.

DTS falls into four different categories:

• DTS 6, the most commonly used 5.1 standard, which can encode six-channel sound with less compression than the Dolby Digital standard. The first five channels are used for the satellite speakers, while the last is reserved for the subwoofer. These devices are normally identified by the presence of this logo:

• DTS ES (Digital Theater Sound Extended Surround), 6.1 standard which uses an additional rear channel (rear central). DTS ES uses less compression than Dolby Digital EX.

The DTS ES standard has two variants:
o DTS ES Matrix, which has a seventh channel interpolated with the primary channels. This is called "virtualisation".
o DTS ES Discrete has an seventh independent channel.

• DTS 24/96 represents an audio format used for storing high-definition music with several channels. This format is primarily used in DVD Audio, or audio tracks which accompany video DVDs. The name comes from the fact that the tracks are recorded in 24 bits at 96 kHz. It may be in either stereo or 5.1.

• DTS Neo:6 is a format for upmixing (virtualising) from a stereo sound source.

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Dolby Digital

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 Digitalis 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.

The difference between Dolby Digital (AC-3) and DTS is:
Both systems are great but statistics for reference only..

• 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)