By Anne Jimkes
While some might not be aware, sound is 50 percent of the experience in VR, as well as in film, television and games. Because we can’t physically see the audio, it might not get as much attention as the visual side of the medium. But the balance and collaboration between visual and aural is what creates the most effective, immersive and successful experience.
More specifically, sound in VR can be used to ease people into the experience, what we also call “on boarding.” It can be used subtly and subconsciously to guide viewers by motivating them to look in a specific direction of the virtual world, which completely surrounds them.
In every production process, it is important to discuss how sound can be used to benefit the storytelling and the overall experience of the final project. In VR, especially the many low-budget independent projects, it is crucial to keep the importance and use of audio in mind from the start to save time and money in the end. Oftentimes, there are no real opportunities or means to record ADR after a live-action VR shoot, so it is important to give the production mixer ample opportunity to capture the best production sound possible.
This involves capturing wild lines, making sure there is time to plant and check the mics, and recording room tone. Things that are already required, albeit not always granted, on regular shoots, but even more important on a set where a boom operator cannot be used due to the 360 degree view of the camera. The post process is also very similar to that for TV or film up to the point of actual spatialization. We come across similar issues of having to clean up dialogue and fill in the world through sound. What producers must be aware of, however, is that after all the necessary elements of the soundtrack have been prepared, we have to manually and meticulously place and move around all the “audio objects” and various audio sources throughout the space. Whenever people decide to re-orient the video — meaning when they change what is considered the initial point of facing forward or “north” — we have to rewrite all this information that established the location and movement of the sound, which takes time.
Capturing Audio for VR
To capture audio for virtual reality we have learned a lot about planting and hiding mics as efficiently as possible. Unlike regular productions, it is not possible to use a boom mic, which tends to be the primary and most naturally sounding microphone. Aside from the more common lavalier mics, we also use ambisonic mics, which capture a full sphere of audio and matches the 360 picture — if the mic is placed correctly on axis with the camera. Most of the time we work with Sennheiser and use their Ambeo microphone to capture 360 audio on set, after which we add the rest of the spatialized audio during post production. Playing back the spatialized audio has become easier lately, because more and more platforms and VR apps accept some form of 360 audio playback. There is still a difference between the file formats to which we can encode our audio outputs, meaning that some are more precise and others are a little more blurry regarding spatialization. With VR, there is not yet a standard for deliverables and specs, unlike the film/television workflow.
What matters most in the end is that people are aware of how the creative use of sound can enhance their experience, and how important it is to spend time on capturing good dialogue on set.
Anne Jimkes is a composer, sound designer, scholar and visual artist from the Netherlands. Her work includes VR sound design at EccoVR and work with the IMAX VR Centre. With a Master’s Degree from Chapman University, Jimkes previously served as a sound intern for the Academy of Television Arts & Sciences.