Tom Parnell, from the BBC’s audio research team, takes us through the project
Can you sum up the pilot for us?
Last year we created binaural mixes of a selection of Proms performances, but this year we’ll be streaming whole concerts in binaural sound, live from the Royal Albert Hall. It’s a 320kbps AAC audio stream and you can listen using normal headphones or in-ear buds. Just make sure you wear them the correct way round, with the left channel on your left ear, and the right channel on your right ear.
What will I hear?
Hopefully you will get an enhanced spatial impression of the Proms, much like being at the hall in person. You will only hear audio when there is a concert being streamed on the experiment. You will not hear “normal” BBC Radio 3 - this experiment tries to recreate the experience of being at the Royal Albert Hall in London, so you won't get the announcements before or during the programme or the interval talk. But you will hear the music and, hopefully, a good sense of the Royal Albert Hall acoustic and the audience surrounding you.
How was it made?
It’s a collaboration with the Radio 3 studio managers who balance the live concerts. Mic feeds are taken from their Radio 3 mix and re-panned in three dimensions using custom binaural software. This is encoded into a DASH stream delivered via the BBC Standard Media Player on Taster. Unfortunately the experiment doesn’t work on iOS devices.
Any challenges and what were the solutions?
Historically, binaural recordings have only been possible using a dummy head microphone. This has limitations because you have little aesthetic control over the mix beyond where you put the microphone. We can now achieve more control over the mix of each musical performance using binaural signal processing. With these new tools we can apply the appropriate binaural filter to each of the Royal Albert Hall mic signals to convince our brains that the sounds are coming from particular directions. Mixing all those signals with our 3D microphone array lets us adapt the final audio output to the character of the piece.
We can also simultaneously generate different surround mixes for loudspeakers, which is another advantage of this new microphone array and post-production technique. This was not possible before and is a key part of our future research into object-based broadcasting.
What are you hoping to prove to and learn from your audience?
We want to provide a new, special experience for the many listeners who use headphones to enjoy the Proms - hopefully one that portrays the music really well, and gives more sense of presence at the live event.
Which Proms concerts will be streamed in this experiment?
If you miss out on any of the following performances you can catch up here.
Prom 1 - 14 July, 7.30pm
Prom 6 - 18 July, 7.00pm
Prom 7 - 19 July, 7.30pm
Prom 12 - 23 July, 6.00pm
Prom 13 - 24 July, 7.30pm
Prom 21 - 30 July, 7.00pm
Prom 22 - 31 July, 7.30pm
Prom 23 - 1 August, 7.30pm
Prom 29 - 6 August, 6.00pm
Prom 37 - 13 August, 6.00pm
Prom 38 - 13 August, 9.45pm
Prom 43 - 17 August, 6.30pm
Prom 44 - 17 August, 10.15pm
Prom 46 - 19 August, 7:30pm
Prom 47 - 20 August, 1.00pm
Prom 54 - 25 August, 6.30pm
Prom 60 - 29 August, 7.30pm
Prom 71 - 6 September, 7.00pm
Prom 72 - 7 September, 6.30pm
Prom 73 - 7 September, 9.30pm
Prom 75 - 9 September, 7.15pm