As I intended Scotscapes to sound immersive and environmentally-authentic, I recorded many sounds using my H3-VR recorder in Ambisonics B-Format or “WXYZ”. Ambisonics is a 4-channel format, which allows the “…recording, mixing and playing back of audio in a three dimensional, 360°…” sphere with sound emanating from different directions around a center point. (Waves Audio, 2017a).
Given the difficulties in accurately perceiving more than two positional cues in a space at a time (Taylor, 2016), I tailored my production process and moved away from recording exclusively in Ambisonics towards recording mono, stereo and Ambisonic tracks. My rationale for this was that not all of my sounds are “soundmarks”, signposting the listener as to their environs. This approach provided me with more panning control and produced less, conflicting background cues for the listener, allowing the Ambisonics tracks to breathe in the mix. My overall Ambisonics mixing approach entailed my use of EQ, compression, time domain effects and so on, however, I perhaps erred on the conservative side so as not to lose subtle dynamics and frequencies in the 360° soundfield. (Waves Audio, 2017b).
One of the most challenging aspects of my project was deciphering the ins and outs of the Ambisonics mix and play back process, having no prior experience. When I first imported my recordings into Pro Tools Standard, I could not monitor in Ambisonics and subsequently discovered that it would only be possible using my headphones with Pro Tools Ultimate (Avid, 2021) and a plug-in like Waves NX Virtual Mix Room, which reproduces the 360° soundfield by decoding Ambisonics channels. (Waves Audio, 2017a). Another challenge I had to overcome during the mixing process involved incorporating mono and stereo tracks into my Ambisonic mix. I mistakenly thought that I could route all non-Ambisonics tracks to a quad output and simply use the Pro Tools panner to position individual tracks within the NX soundfield. (Waves Audio YouTube, 2017). Upon carrying this out, however, I realised that my panning moves were not translating to NX and that I would require an Ambisonics encoder for mono and stereo tracks to position these accurately within the 360° sphere. (Waves Audio, 2017a). I learned how to incorporate my mono and stereo tracks into the 360° soundfield by applying Waves’ B360 Encoder and using its in-built panner to vary the rotation, width and elevation of each track. I employed these tools creatively to sonically reflect the visual movement of the piece (Ibid, 2017b); for example, from 3.19 – 3.24, I automated the bench sticks’ rotation below to mirror on-screen movement and enhance the immersive narrative.
Another instance of my sonic reflection approach can be seen in my automation of the NX plug-in itself below, where I automated the rotation to have all tracks, including my stream recordings and dialogue, subtly follow the camera angle from 3.25 – 4.02. During the tunnel sequence here, I increased the ambience amount using automation to apply a faint echo to all tracks and accord with the visual.
During the mixing process, a colleague suggested that I could position the voiceover in the front, centre speaker of a 5-stem mix, which, I agreed, may afford it more clarity in the soundfield. I routed my Ambisonic mix to a 5.0 output and fed this to a 5.0/stereo version of NX, shown below.
While placing the voiceover in a 5.0 mix slightly enhanced its clarity, it detrimentally impacted other elements in my mix, as demonstrated in this brief audio comparison: https://soundcloud.com/sonicscotland/sets/ambisonic50-comparison/s-7lmAvT8fcwu. 5.0 audio originates primarily from the left channel, settling in the left, left surround and right surround channels, differing significantly from Ambisonics audio, pictured below, which comes from above/front, settling near the centre of the head to give the impression that whispers are drifting downward into the listener’s mind.
As the 5.0 mix showed “…difficulties representing sound beyond the horizontal dimension…” (Waves Audio, 2017a), I proceeded with the Ambisonics mix as this definitely aligns more with my creative intentions behind the piece.
After mastering, I encountered a slight snag trying to bounce my Ambisonic audio as I attempted to export the mix as a quad file. (Waves Audio YouTube, 2017). Following a colleague’s suggestion however, I downloaded the Waves NX - 3D Audio App, and this allowed me to play back my audio in 360°, which had been bounced from the 2-channel, quad/stereo NX headphone output in Pro Tools.
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