3D Audio. Our Vision.Over the past decade, 3D has become a part of mainstream cinema. Today, we see more and more TV programs and live events shown in 3D. The visual part of the experience has changed dramatically. The same can't really be said for sound. Until now.
Introducing 3D Audio
Many commentators suggest 3D audio offers a similar step change to what has occurred with 3D visuals. Our CEO says it’s more than marketing hype.
Love them or hate them. 3D visuals are here to stay, and now they are being used not just to create neat effects but to really enhance the viewing experience. Once you’ve seen a live event in true 3D, it’s difficult to go back. But, what about 3D audio? It’s the hot topic at the moment. Is it here to stay or just a passing fad?
As the people who developed the audio processor for the new Auro3D system in partnership with Barco, Datasat Digital Entertainment is totally committed to 3D audio. Not because it is the great new thing but because it is a natural extension of audio technology. It is a relatively small step to reap an incredibly big reward.
Major Breakthroughs in Sound
The history of cinema sound has seen two major breakthroughs: the move from mono to stereo sound and then the move from stereo to surround sound. Since its introduction in the early 1990s, the basics of surround sound haven’t really altered substantially. The original 5.1 arrangement is still the most commonly used while the introduction of 7.1 or 8.1 has helped to improve the depth of the sound delivered.
Sound, as we all know, is perceived in three dimensions. If we plot it as a chart, the X axis equals width, the Y axis equals depth and the Z axis equals height. Surround sound – and improvements to surround – has focused on the X and Y axes. It has stayed rooted in the horizontal plane. That’s not to say that great improvements have not been achieved in the quality and transparency of the sound. They have. It means that we have looked to some fairly sophisticated psychoacoustic techniques to create a ‘virtual’ 3D sound experience.
The Focus on Height
The most recent developments in 3D audio have focused on the Z axis. Put it another way, we have brought height into the equation. In a basic 9.1 configuration, that means having four sets of speakers positioned one above the other at each corner with a central speaker and sub-woofer in the middle. The system is arranged and tuned to provide a wide listening sweet spot that gives a highly natural and immersive experience.
Focusing on height is hardly a new idea. I’d imagine most cinema sound engineers have had interesting results with their ‘voice of god’ installations. What is new this time is that we are able to create a sound stage that is as close to as a natural listening experience than has ever been possible before. The result is not just the direction and amplitude of a sound event but the relationship between sound events. The listener is able to perceive footsteps approaching from behind left while a car drives off in the right distance. The experience should seem as it does if the listener was standing on an actual street corner.
Our Room Optimization Technology
Of course, 3D audio is more than simply how you position your speakers. There are any number of enhancements on how the sound is processed for output so that the listener is provided with an optimized ambient sound environment that feels remarkably like the real world. The listener feels like they are the main observer in any scene.
To achieve this effect in a cinema requires more than the basic 9.1 arrangement. With Auro3D, Datasat Digital Entertainment developed our AP243D audio processor delivering 16 channels of input and output. This has enabled Barco to deliver 3D sound to cinemas in 11.1 and 13.1 formats. It also enables flexibility in arrangement to 12.4 and beyond. Our room optimization technology and experience allows us to produce the ideal 3D sound experience for the widest array of output configurations and listening settings.
The First Full 3D Audio System
The other feature of Auro3D that helps the widespread adoption of 3D audio is the ability for a cinema exhibitor to introduce the system without a major ‘rip it up’ investment strategy. Most will be able to adopt 3D sound with only small changes to their existing systems. Barco has developed the system so that the full 3D sound is folded down into a 5.1 format at the mixing stage. The 3D audio information is held with the 5.1 file and only plays when a Auro3D output system is available. Otherwise the sound will play perfectly on the surround system available. This allows cinemas to implement a gradual transition from surround to 3D audio.
Auro3D may be the first full 3D audio system but it won’t be the last. In reality, all our audio processors for professional cinema and home cinema are already capable of accommodating 3D audio. The development of 3D audio will be driven at the creative end. The film producers, TV stations and record companies that want to deliver the best, most natural sound to their listeners will increasingly adopt this style of sound recording and mixing.
Natural and Immersive
This is what will move 3D audio past the ‘fad’ label. We saw a rash of albums recorded in ‘3D sound’ in the early 1990s and there have been little bits and pieces since. But, the reason that these developments didn’t gain critical mass was that they focused on the technique as an effect. Today, 3D audio is being used to enhance the listening experience by making it natural and immersive. In addition, it is not simply a series of isolated technological developments. We are seeing developments in 3D audio across content types as cinemas and home consumers look to integrate a wide variety of content types into single multi-channel systems.