Previously, we looked at how integrated loudspeaker solutions that leverage network connectivity, like Fohhn’s AIREA, can be used to implement affordable immersive audio systems in smaller venues. Part II looks at immersive audio processing options that exist outside of the expensive world of proprietary hardware and can be incorporated into the creative artists’ or engineers’ workflow.
Firstly, let’s define why a venue would even want this capability. Quite simply, it allows the venue to host a wider range of events, therefore creating more opportunities for revenue. A sound system installed to cover voice and music amplification can also be used for spatial audio with a bit of forethought and creativity. As the technology that supports spatialisation is now available at low cost or even for free, more and more content will be created that exploits it. Venues that are ready for it will benefit.
From the creator’s point of view, spatialisation is an opportunity to work in a new field and get completely new results. Artists will always push the boundaries and will colonise this space as it becomes available to them. From an engineer’s perspective, spatial audio systems create a more accurate reproduction of an artist’s work and offer more tools to create an outstanding aural experience for the audience.
Interfaces for Spatial
So what do you need and what is available to start mixing audio to an immersive system? Firstly, your audio interface is going to need multiple outputs to feed the independent buss outs that each amp and speaker requires in an immersive mix. UAD’s Apollo x6 and Apollo x8 are good examples; the x8 has eight line outs, 12 channels of ADAT out, and a stereo SPDIF out. The x6 has six line outs and the same digital output structure as the x8. Both can be daisy-chained via Thunderbolt with up to three other Apollo interfaces to create even larger systems.
Processing with Envelop
Next is the spatial processing itself. Most sound designers and leading electronic musicians use Ableton Live for this type of creative work. An artist-led non-profit organisation called Envelop, based in the USA and dedicated to exploring immersive audio, have released a free and complete set of tools for spatial audio using the Max for Live platform that is included in the Ableton Live 10 Suite.
Envelop’s set of plugins for Live include a master bus device that scales your outputs to match the system you’re connected to, a mixer capable of 3D panning, a device for automating an audio object’s motion through space, tools to playback files already encoded with spatial information (e.g. Ambisonic .wav files), a 3D reverb and a 3D delay, plus metering. Envelop have also created EnvelopLX for lighting control of the LED rigs in the immersive audio venues they run, which can be controlled in turn from their Ableton Live plugins.
Outside of live immersive sound, new tools are constantly being developed for VR and AR, mainly targeting the gaming industry. A search for ‘spatial audio’ on software development platform github.com will return hundreds of results, with developers constantly creating new tools for spatial’s new workflows. Some of these projects go way beyond binaural and Ambisonic mixing for headphones; SoundScape Renderer is one such project.
SoundScape Renderer is open-source software developed in Germany that can be controlled via its own GUI, via a Max for Live plugin, or even from an Android app. Apart from being able to be used for different types of binaural synthesis, it can be used for Wave Field Synthesis (WFS) and Vector Base Amplitude Panning (VBAP), which are both applicable for live spatial reproduction. Being open-source and developed by a passionate community of audio researchers, SoundScape Renderer is free to download.
The Future is Immersive
Projects like Envelop and SoundScape Renderer are heralding in a new era in live sound that will be driven by musicians and sound designers that don’t have access to the expensive proprietary spatial audio systems currently being used by big-name, big-budget acts. As the use of these tools becomes more common, stereo mixing is very quickly going to sound limited and regressive.