Virtual Reality Sound: Deconstructing and Reconstructing Reality
Virtual reality is uncharted territory in many ways, but the trend is predicted to grow rapidly within the next ten years. Currently, there are a plethora of apps and companies interested in growing virtual reality even further, but for now, the landscape does not extend beyond the experimental realm. One of the biggest challenges of virtual reality is that to increase the sense of immersion, not only because of the need for graphics (realistic enough to trick the brain,) but the sound that produces an absolute sense of reality.
This problem is an obstacle facing any company interested in working with such technology, whether in the field of video games, film, television, and entertainment, in general, as well as flight simulators, virtual tourism, or distance education, among others.
The sound we are talking about here is known as 3D, and it consists of a new paradigm for all professionals in the sound industry, like Enhanced Media. Let’s see what it is all about.
And let’s start by clarifying that this audio format is actually not new. Its origin dates back to several decades ago but currently, multiple manufacturers are implementing it to produce a turning point in terms of sound quality; specifically, to the sound that can be perceived with headphones: the devices that best fit this type of audio. What strikes us most about 3D sound is the effect produced through the headphones which simulates the arrival of sound from various points “in space”, as if we were in a room surrounded by speakers. When trying it out, the difference is easy to appreciate and surprises most first-time listeners.
This trend is making a comeback and is more valuable than ever due to the rise of virtual reality and next-generation video games, which tend to enhance surround effects. But 3D audio technology can be applied to all kinds of sounds, including music, of course. In fact, several brands are looking for a new technology to keep selling and surprising their users, and this 3D sound has all the ingredients to become a determining factor.
When we think of virtual reality, what pops in our minds is a VR viewer and motion controls, for sure, but it is important to clarify that there are more senses than sight involved, at least, when we talk about creating an immersive experience. Sound, as well as its distribution and execution in a virtual simulation can lead the user to experience more realistic situations. The visual aspect of VR simulations is easy to understand and process even if it seems too sophisticated. Wherever you turn, as a viewer, the software will reproduce a three-dimensional world taking into account the position of your head and eyes. Similarly, the motion controls will be drawn in relation to your hands. However, the way we process sounds is not so obvious.
Small differences in volume and position generate the concrete reference of a position in space regarding the sound sources. The explanation is simple: there are small differences between what each ear hears, which are interpreted by our neurons and assigned a position relative to us. Thus, we are able to identify the origin of a sound even when we do not make visual contact with what is producing it. For example, our closeness to a sound source can be controlled by the intensity: The louder the sound, the closer the brain perception of it. Now, when using stereo headphones, we can control which side it comes from in the same way. So, we can place left or right depending on the volume of each speaker.
So, the clearest question we can ask ourselves is: how does virtual reality sound really work? What is the technique used? The explanation is based on the distance between our ears, which is why the 3D sound is mainly heard through headphones. The fact of having to use it through headphones has been one of the main reasons why its use has not spread as fast as we would like. In music, we normally look for the sound to be heard as close as possible through any device, but, in the case of 3D audio, if we do not have a headphone, the music would be heard very differently, and this is because this type of sound modifies different parameters, such as frequencies or time lag. In headphones, you can adjust the position well, but through the speakers, it is a bit more complex than that.
To create the 3D audio effect, what is done is to “trick” the brain into positioning certain frequencies in space. In other words, the audio file is modified by copying the frequency spectrum and other parameters that our ears would hear if we were surrounded by sound sources, such as instruments. In other words, it is a matter of deconstructing and reconstructing the sound reality. It is not a simple job.
