A surround amplifier is able to provide sound in surround quality as Dolby Digital. A stereo amplifier will as it say only provide stereo sound.

THX is the trade name of a high-fidelity sound reproduction system for theatrical movie theaters, screening rooms, home theaters, computer speakers, gaming consoles, and car audio systems. THX was developed by Tomlinson Holman at George Lucas's company Lucasfilm in 1983 to ensure that the soundtrack for the third Star Wars film, Return of the Jedi, would be accurately reproduced in the best venues.

Each THX Certified Product is engineered to perform best in specific room environments. Room size, acoustic design and system setup are all critical factors to how movies, music and games are experienced in the home.

THX Ultra2 Certified Products are engineered and designed for large home theaters. Viewing distance of approximately 12 feet / 4 meters from the display to the listening position.

DVD-Audio (DVD-A) is a Digital Versatile Disc (DVD) format, developed by Panasonic, that is specifically designed to hold audio data, and particularly, high-quality music. The DVD Forum, consisting of 230 leading companies worldwide, released the final DVD-A specification in March of 1999. The new DVD format is said to provide at least twice the sound quality of audio CD on disks that can contain up to seven times as much information.

DVD-A also provides more complexity of sound by increasing the sampling rateand the frequency range beyond what is possible for the space limitations of CDs and DVD-Video. DVD-Audio is 24-bit, with a sampling rate of 96 kHz; in comparison, DVD-Video soundtrack is 16-bit, with a sampling rate of 48 kHz, and standard audio CD is 16-bit, with a sampling rate of 44.1 kHz.

Although DVD-A is designed for music, it can also contain other data, so that - similarly to enhanced CD - it can provide the listener with extra information, such as liner notes and images. A variation on the format, DVD-AudioV, is designed to hold a limited amount of conventional DVD video data in addition to DVD-Audio. DVD-A is backed by most of the industry as the technology that will replace the standard audio CD. The major exceptions are Philips and Sony, whose Super Audio CD (SACD) provides similar audio quality. Like DVD-A, SACD offers 5.1 channel surround sound in addition to 2-channel stereo. Both formats improve the complexity of sound by increasing bit rates and sampling frequencies, and can be played on existing CD players, although only at quality levels similar to those of traditional CDs.

Digital Theater Systems, a company which produces multichannel audio systems for cinema and home video, refers to an 6-channel audio system.

A 6-channel surround sound system developed by Dolby Laboratories. The audio is separated into front left, center, front right, rear left, rear right, and low frequency effects.