AMBEO for Interactive Experiences

Take your XR production to the next level with immersive audio.

Introduction

AMBEO for Interactive Experiences is a flexible solution for the recording and creation of immersive audio ambiences. Recording complex ambient environments is made easy through the use of the Sennheiser AMBEO VR Mic, which allows for creators to capture the true sound of a location using a single microphone. By using recordings from a Sennheiser AMBEO VR Mic as a base and adding other sound effects and signals from spot microphones, game sound designers can create complex and flexible background beds for console, computer and VR/AR video games while using less computational resources then individually rendered spot sources. The techniques described below work best for things like music, ambient sound, and other background sounds that a player wouldn’t interact with in a game.

AMBEO VR Mic

Workflow

Blueprint

Capturing

A single compact microphone operating on the Ambisonics principle, it allows you to capture complete spherical audio from a single point in space. Basically, you capture exactly what a listener would hear if he or she was in that position. This technique allows you to capture hard to recreate soundscapes, such as the interior of a race car or any other particular acoustic environments.

It sounds easy but some care should be taken to record the Ambisonics signal correctly with regard to position and level, as certain errors cannot be corrected during post-production. A field recorder that has an AMBEO VR Mic mode will help to make this task far easier.

On location, the AMBEO VR Mic will usually be combined with conventional microphones such as wireless lavalier mics. This allows for increased flexibility during post-production, giving the mixing engineer greater control over the ambient mix.

Mixing

DAW and tool chain
Mixing your Ambisonics bed can be done in most standard DAWs as long as they support multichannel tracks, i.e. a minimum of four channels in a track. To support you in the mixing process, you should select an Ambisonics tool chain. With Dear Reality’s advanced software tools, you create outstanding audio productions with a true perception of direction, distance, reflections & reverb.

Recommended mixing paradigm
Use the recorded Ambisonics signal as the base ambience, then add signals from conventional microphones such as wireless mics and foley sound to emphasize and build your final ambient bed.

Format conversion
As all Ambisonics tool chains operate in B-format, you first need to convert the AMBEO VR Mic signal to B-format using Dear Reality's free dearVR AMBI MICRO. The Ambisonics plugin offers an optimized A-to-B conversion perfectly matched to the Sennheiser AMBEO VR microphone and lets you select different mic orientations, providing a deeper access to your soundfield.

Spatialization
Additional sound sources captured by conventional microphones need to be spatialized so that they come from the correct point in space and match the video image and the ambience. This step is accomplished using the state-of-the-art spatializer plugin dearVR PRO. The advanced immersive panner lets you position audio sources anywhere in the immersive soundstage surrounding the listener. Behind or in front, above or below, to the left or right, closer or farther away.

Monitoring
During mixing, it is important to monitor your Ambisonics mix. You can easily decode your mix in your DAW using a binaural renderer like dearVR AMBI MICRO. The best practice is to use the renderer that will eventually be integrated into your final game.
For deployment to a traditional game in either stereo or 5.1, the Ambisonics signal must be decoded to loudspeakers. We recommend HARPEX X, a partner of Sennheiser, to decode the signals to various loudspeaker arrangements.

A note on working with Ambisonics
Ambisonics is the description of a sound field. Therefore, you should never work on any of the constituent tracks of an Ambisonics signal on its own. Always use Ambisonics mixing and editing tools if you want to modify an Ambisonics signal. When using a standard multichannel mixing tool, you must make sure that changes are applied equally to all four channels – otherwise you risk altering the spatial image of the Ambisonics signal.

Delivery

Console and Computer Games
Ambisonics is a versatile format that can be decoded to suit different playback environments from mono to 5.1, 7.1, or any other arbitrary speaker arrangement. Some plugins exist for game engines that allow for loudspeaker decoding directly in your app, but you can be equally served by pre-rendering your Ambisonics mix into 5.1 or whatever speaker arrangement you’d like to deliver. We recommend processing your signal using HARPEX X. Once the signal has been decoded, bring it into your middleware or game engine as you would any surround sound audio file.

VR/AR Games
When working in the Unity game engine, Dear Reality’s dearVR UNITY spatializer lets you create ultra-realistic acoustic environments with a true-to-life perception of direction, distance, reflections, and reverb. All dearVR spatializer plugins rely on Dear Reality’s advanced dearVR CORE engine, resulting in best-in-class externalization and realistic immersion.

Most game audio middleware and game engines natively support Ambisonics to binaural decoding. Please see the documentation of the game audio tools you expect to use to see what formats they support and how their Ambisonics support works. As all of the sound sources in your ambient bed is “pre-baked” into the Ambisonics signal, you can save significant computational resources by rendering a single Ambisonics bed instead of having many individually rendered sound sources.