CLOSE-UP- An Internet News Magazine for Broadcast Professionals

Joe Fedele

If you have a more than passing interest in both cinema and home theatre sound reproduction, it's likely that you will encounter most, if not all, of the following terms:

Acoustics: The characteristics, such as how sound is reflected and absorbed, that acoustically differentiate one environment from another, such as a living room from a concert hall.

Ambiance: Low level sounds that set a mood or suggest the character of a particular place.

Atmospherics: Background sounds, such as wind, rain, or traffic noise, which add to the reality of a scene. These sounds are sometimes recorded right at the shooting location, creating what's called a wild track which is later mixed into the final soundtrack.

Dolby Stereo: Dolby Laboratories' umbrella term for its film sound technologies.

Dolby Surround: The home surround-sound format derived from Dolby Stereo film sound.

Dolby Surround Digital: The upcoming multichannel digital format for home theatre and HDTV derived from Dolby Stereo Digital film sound.

Dynamic range: The range between the loudest and softest sounds a sound format or system can reproduce.

Effects: Sound effects, i.e., the non-musical elements on a soundtrack other than dialogue.

Foley: The art of recreating incidental sound effects, such as footsteps or rustling clothes, in sync with the picture. Named after one of its first practitioners.

Mix: As a noun, the blend of dialogue, music, and effects which comprises a film's soundtrack. As a verb, to assemble these elements into a soundtrack.

Optical soundtrack: Narrow, clear stripes adjacent to the picture on a 35 mm movie print which vary in width according to the sound. In the projector, they are scanned by a narrow light beam in order to create the electrical signals which ultimately reach the theatre's speakers. 70 mm prints use another soundtrack technology called magnetic striping, which provides six sound channels. Sound quality is very high, but so is the cost of a release print.

Pro Logic: The more advanced form of Dolby Surround that not only recovers the surround information from encoded program material, but also adds a center channel to keep dialogue and center effects firmly positioned on the television screen. Pro Logic permits a wider listening/viewing area, provides better channel separation, and gives more accurate sonic perspectives.

SR•D: The term the film industry uses to identify 35 mm release prints containing both an analog Dolby Stereo SR ("SR") and Dolby Stereo Digital ("D") optical soundtracks. The term is sometimes misused to identify just the Dolby Stereo Digital format or presentations.

Stereo: From the Greek word for solid; identifies sound recording and reproduction by more than one (mono) channel. In home music reproduction, "stereo" came to mean two channel sound. In the film industry, however, "stereo" came to mean at least four channels (left, center, right, and surround). This is why Dolby's film sound technology could be identified simply as Dolby Stereo for the film industry, and why a new term, Dolby Surround, was needed to identify multichannel home sound reproduction.

Surround sound: The reproduction of ambiance, atmospherics, and occasional special effects anywhere around the listener by means of multichannel sound reproduction.

THX: A trademark licensed to movie theatre and manufacturers of home theatre products, identifying compliance with the performance parameters of Lucasfilm Ltd. for commercial and home theatre sound systems. Unlike the Dolby Stereo and Dolby Surround trademarks, THX does not identify soundtrack formats and processes. THX-certified theatre use professional Dolby Stereo processors for playing Dolby Stereo films (which is why you may seen both logos on theatre marquees). THX-licensed home theatre processors are all based on Dolby Pro Logic Surround decoding.

Time Link: A high-quality, yet economical, digital audio delay technology developed by Dolby Laboratories and used in some Dolby Surround decoders.