1. What is spatial audio?
Spatial audio is a way of creating sound in 360 degrees around a listener. Sound can come from any place in a sphere.
It takes two forms - binaural and object-based. Binaural sound is used in headphones. Object-based sound is for television, radio and loudspeaker listening.
The BBC has used spatial audio to record the BBC Proms, Doctor Who and the Turning Forest VR fairy tale. It can be used as part of 360 video, standard video or radio. This guide is to help producers explore how to use spatial audio in their productions.
2. How does spatial audio sound?
Spatial audio is so similar to what we hear in real life, it has the potential to immerse the listener more fully than standard audio. BBC Academy technology trainer, John Heraty, demonstrates. Put your headphones on.
Be aware some laptops have channel reversed headphone sockets. Use the channel ID at the beginning to find if your headphones are correct. Simply swap them round if not.
3. Which microphone should I use?
Click on Choose to learn more about your microphone options.
4. What are the rules and pitfalls?
Don't use spatial audio for its own sake. Ask how it will improve the storytelling. Will it add atmosphere, drama, thrill or fear?
Use a dummy head and microphone to practise your sound before recording.
Line up your sound with the shots
Make sure the source of the sound is in line with what the viewer can see.
Use it consistently
Turning the spatial element on and off becomes distracting. Use it throughout for atmosphere and emphasise it when making a point.
Don't combine microphones
Don't try to mix binaural microphones with lapel and boom mics unless you intend to synthesise them in post-production.
Be aware of distance
In post-production with a mono mic, ensure you alter the sound as the source moves nearer to, further from or around the camera.
6. How do I start?
Binaural or object-based?
To experiment it's easiest to start with binaural sound. You can capture spatial audio using simple in-ear mics. Little can be changed in post-production but you can create good effects using free software plug-ins which can be used with most digital audio workstations and will allow steering of mono sounds around the listener. To include spatial audio in a future programme, object-based audio is the best solution. Object-based audio involves capturing sound using mono mics that are moved in space during post-production. BBC R&D is developing standards for object-based audio files. These will be future-proofed and can be re-purposed for any platform.
BBC staff wanting advice should contact:
- Chris Pike, BBC R&D lead audio engineer
- Tom Parnell, BBC R&D research studio manager, audio team
- John Heraty, BBC Academy technology trainer
Sign up for the spatial audio course
The BBC Academy has launched a spatial audio course for BBC staff. Its aim is to create competent spatial audio studio managers, sound operators and producers. Speak to John Heraty for details.