Binaural and immersive audio technology currently in use includes methods to record sound binaurally using microphones and ‘dummy head’ arrays designed for the purpose, and software plug-ins to enable audio mixing in binaural and 360 degree formats, such as DearVR and Facebook Audio Spatial Workstation. Replay of the formats is achieved using headphones for binaural recordings and arrays of loudspeakers for 360 degree audio such as those specified in the Dolby Atmos specification.
Binaural recording is performed on location or in studios with the use of pairs of microphones spaced to simulate human ears, either as part of a dummy head or on spacer mounts, with replica ear pinnae to facilitate accurate recordings of sound as a person would actually perceive it. The Neumann KU-100 dummy head and the 3Dio FS Pro 2 are current examples.
The 2-channel recording is replayed on headphones to delver the sound directly to the listener’s eardrums to maintain fidelity and permit the listener to experience the immersive qualities of Binaural audio.
Multiple mono or stereo sources can be combined in studios to create binaural or surround sound mixes. These require software plug-ins that can simulate panning in three dimensions: left-right, front-back and up-down. By panning and with judicious use of reverberation and other effects, the immersive audio experience can be constructed.
Two examples of these plug-ins are DearVR and Facebook Audio Workstation.
In my Immersive Audio assignment for my MSc Audio Production course at the University of Salford, I used DearVR Micro to create a binaural mix of an excerpt from a track I am working on: Noah’s Castle Rebuilt – Paul Grooveside – Binaural Headphones Mix for MSC.
In the mix I placed a mixture of acoustic and synthesised percussion instruments around the listener and at varying heights, the claves and cymbals were panned high, congas and toms lower. Some guitars were panned behind the listener, synthesizers ‘wrapped’ around the sound field, bells placed around the listener and distanced using reverb effects panned through DearVR Micro. I initially found the mix to be complex to set up, so simplified it to make it clearer and more accessible to the listener.
Dolby Atmos is a development of previous surround-sound replay systems which adds height to the placement of objects in the sound stage by mounting loudspeakers above the listener as well as around them on the same level. Sounds are treated as ‘objects’ instead of conventional panned channels. Digital processing of the objects renders the sounds in the context of the known configuration of loudspeakers in each theatre, thus enabling precise and accurate sound placement for each environment. By digital panning, sounds can thus be given the illusion of coming from any location in the sound stage around the listener. Dolby Atmos cinema systems are closely specified and must be calibrated accurately to be certified as meeting Dolby standards. The technology is becoming available for home cinema systems, although it is still expensive.
References
Korff, C. (2021). An Introduction To Binaural Recording: Use Your Head. Soundonsound.com. https://www.soundonsound.com/techniques/introduction-binaural-recording
Neumann Berlin. (2021). Dummy Head KU-100. Neumann.com. https://en-de.neumann.com/ku-100
Rode Microphones. (2021). NT-SF1 Soundfield by Rode. Rode.com. https://en.rode.com/ntsf1
Dear VR. (2021). Dear VR Micro. Dear-Reality.com. https://www.dear-reality.com/products/dearvr-micro
Facebook 360. (2021). Spatial Workstation – Facebook 360 Video. Facebook 360fb.com. https://facebook360.fb.com/spatial-workstation/
Paul Grooveside 