Anticipating Seamless Sound
Once upon a time, film sound consisted of one channel: mono sound. In 1940, Walt Disney astounded the world by presenting his groundbreaking film Fantasia in four-channel sound via a system called FantaSound (developed by RCA). Stereo arrived in force in the 1950’s, and the next change came in 1969 with Michael Wadleigh’s Woodstock, which was also in four-channel, but in a configuration different from Disney’s. In 1979, Apocalypse Now gave us full 5.1 Dolby surround sound. Today, 5.1 continues to be the standard format in which most films are released, but 7.1, which adds two more channels, is quickly gaining momentum in more modern movie houses.
Audio has come a long way in the last half-century or so, but what about the next 50 years? What will film audiences have to look forward to when they walk into the theater of the future? Gazing into the crystal ball is a notoriously dangerous pastime, and trying to divine the future of film sound doubly so. However, if we look at the rate of progress we’ve made over the past few years, there are some educated guesses we can safely (more or less) make.
Some theorists have proposed a multi-speaker array far beyond today’s 5 and 7 channel audio, with upwards of 250 individual and discreet loudspeakers arranged around the theater space. It is commonly thought that being able to control, amplify, and present such sound is highly unlikely, but sound artist installations have been surmounting this challenge for decades. For example, as early as 1958, Edgard Varese composed his Poem Electronique for the Brussels World’s Fair utilizing over 400 discreet audio channels.
But even utilizing such arrays, theater audiences still don’t accurately experience sound as it would take place in the real world. One of the ongoing problems with film sound, even with a multi-speaker array, is that the sound is presented on a plane. In other words, the speakers are arranged at a constant height around the theater space. In our everyday lives, on the other hand, sound engulfs us and comes from everywhere – above, from the sides, from the rear, even from the ground. Although some installations, such as IMAX, contain speakers above the screen as well as behind the screen and around us, they don’t give the convincing illusion of the real world.
Of course, some believe that film audio should not attempt to recreate the real world, since film is an art form that represents the world from a specific vantage point. But if we take for granted that realistic, natural-sounding audio is something to strive for, here’s what I would propose: a three-dimensional, “holographic” approach to sound reproduction.
To better understand what I mean by holographic sound, imagine a 3D polygon standing before you. In a holographic sound theater, the audience would be on the inside of that hologram. Rather than having localized points of sound scattered around a theater, imagine a room – six planes: four walls, ceiling and floor – with each surface acting as one seamless sound transducer. In a theater of this kind, sound could be placed anywhere on the surface of these planes and move freely to any other point. With this model, the entire theater space would be active in delivering sound to the audience, freeing us from the single-point loudspeaker array that limits us today.
What would the surfaces be constructed of? Hey, I’m in the audio prognostication business here, not material invention! Some sort of flexible polymer perhaps, similar to what is found in the speaker cones of some loudspeakers. But this is 50 years into the future and we have plenty of time to figure that out. What’s important is that if this type of playback technology were to become available, the ways in which craftspeople work and think about the sound would undergo an analogous revolution, and the next great leap in film sound would have arrived.