Loudspeakers and Digital Immersion - Text 5
Finally, in 1977, the Dolby Stereo system’s two sound tracks made it possible for audiences to experience stereophonic sound in adventure and science fiction films such as Star Wars or in a few films which experimented with sound, such as Jerzy Skolimowski’s The Shout (1978).
Stereophonic sound became widespread in the 1980s. As has often been the case, cinema was behind music. Stereo sound on discs for high-fidelity sound systems was developed in the 1970s. In the 1980s, digital sound for music grew, and in the late 1980s the compact disc replaced microgroove vinyl records (which remain a niche market but were not sold in large numbers again before the 2010s). Digital sound did not take its place in movie theatres until the mid-1990s. Immersion was developed using various six-track exhibition systems (5.1). In general, these different processes had two central tracks played from behind the screen, one on each wall to the left and right of the audience, and one in the rear. The sixth sound track, the “.1,” was the subwoofer. This speaker, placed behind the screen, played only the lowest sounds (explosions, engine vibrations, etc.). Immersion by means of digital sound playback was encouraged by the growth of multiplexes, those complexes with at least ten movie theatres built everywhere since the 1990s. In the 2000s, Dolby 7.1 was also introduced in movie theatres, and since 2012 Dolby has offered its product Atmos. A grid of loudspeakers placed on the ceiling, in addition to those spread out on the walls of the theatre, “sprays” spectators with different sound tracks. These “sound objects”[3] can give the impression of movement through the movie theatre by on-screen vehicles or animals. From 30 to 215 loudspeakers (in the Dolby Theatre in Los Angeles) can be placed in the theatre to broadcast ambiences or precise “sound objects.” The Dolby Atmos system manages up to 128 tracks simultaneously. This growth in the number of tracks, heard in movie theatres since the advent of digital sound, is an attempt to improve each spectator’s immersion wherever they are seated in the theatre. Together, these systems seek to promote the movie theatre as an attractive venue in the face of rivalry from smart phones, computer screens, home theatre projectors and widescreen television.
