Acoustical engineering forms innovative sound zones to protect privacy

Ground-breaking research at the University of Southampton has designed a system that creates sound ‘zones’ and targeted background noise.

The new research by postgraduate researcher Daniel Wallace could allow private conversations to be conducted on speakerphone, or personal music preferences to be played, without irritating your neighbour.

Daniel, who is based in Southampton’s renowned Institute of Sound and Vibration Research, says: “When you have a single loudspeaker, that speaker likes to fill the room with sound. That’s fine in normal circumstances, but for certain applications, for example in a bank or on public transport, you want the sound from the speaker to be private.

“Rather than using one speaker, we can use several, so that the sound adds up where you’re standing and cancels out everywhere else. But, like noise cancelling headphones, the cancellation effect is never perfect, there is always a bit of leakage.

“The same is true for this sound zoning system – except in this case, this leakage could include your private information. To beat this, you can use the same set of speakers to focus background noise towards other people.”

Daniel has completed his PhD and is now on a 12-month Doctoral Prize Fellowship funded by the Engineering and Physical Sciences Research Council.

As well as physical acoustics, the research is taking into account the psychoacoustics of how humans perceive sounds into account.

“No-one wants to be deafened by background noise,” Daniel says. “The system needs to provide just enough extra noise to ensure privacy, but not so much that it is annoying. I have designed a system and set of algorithms to do that.”

Read the full article in the latest edition of Re:action, the University’s research and enterprise magazine.