Soton Audio Labs: immersive 3D audio
The average Briton spends nearly a decade of their adult life watching television, but millions of viewers enjoy a limited experience through a small set of loudspeakers. In real life, we hear and locate sounds all around us. This reality can never be truly recreated through our screens or even sophisticated home cinema systems.
Traditional surround sound systems rely on placing a set of strategically placed loudspeakers around the listener. “Although this is good because the sounds can be placed around the edges of the room, it is still a long way from how sounds are perceived in real life,” explains Associate Professor Filippo Fazi. “For example, there is no way a traditional audio system could make you feel like someone is whispering just behind your ear.”
3D acoustical engineers from the University of Southampton’s world-leading Institute for Sound and Vibration Research have invented an innovative solution that will enable listeners to experience sounds coming from any direction within the home from a single soundbar. “Our system, takes the outside world and reproduces it perfectly to your ears, so that you can enjoy a realistic, true 3D experience,” Filippo says.
Soton Audio Labs are able to create this immersive audio experience through an attached camera system which tracks the location of the viewer within the room. “Like ripples in a pond, our technology uses destructive and constructive sound cancellation to deliver a perfect 3D experience wherever you are in the room,” Research Fellow Marcos Simón adds. “Our smart adaptive system can make it sound like a tiger is pacing around you or that someone is talking to you from behind.”
The acoustic engineers have developed two prototypes, the first utilising 30 speakers across a 1.6m frame and the second offering a more compact solution of 16 speakers across a 1m frame. “The prototypes have been shown in audio fairs and conferences and have obtained a great acceptance from experts in the audio industry,” Marcos explains. “Demonstrations with everyday users have also made a big impact with people asking ‘when can I have one of these in my living room?’”
“In order to make our amazing soundbar products available to everyone, we need investment to take it from prototype to a commercial product,” Marcos says. Potential collaborators and investors can get in touch with the team using the contact form on this page.
The soundbar technology taps into binaural methods of recording, which capture audio from two microphones to create a 3D stereo sound sensation for the listener of being in the place where the recording was made. Binaural audio can also be generated by synthesizing mono signals through transfer functions. For example, by combining the eight channels of a 7.1 surround audio system with corresponding transfer functions to access formats of 3D audio.
“Whilst binaural audio is mostly consumed with headphones, it is also possible to listen to it with loudspeakers,” Marcos says. “The first applications of binaural reproduction date back several decades but have needed the appearance of modern digital signal process robustness to become more popular.
“These advances have required listeners to sit in a predetermined sweet spot, limiting its popularity. Now though, it is possible to adapt this sweet spot to the listening position in real time using computer vision systems, making binaural reproduction with loudspeakers an exciting reality.”
Marcos’ work is supported by the Engineering and Physical Sciences Research Council (EPSRC) Programme Grant S3A: Future Spatial Audio for an Immersive Listener Experience at Home (EP/L000539/1) and the BBC as part of the BBC Audio Research Partnership. The S3A programme is a collaborative grant between University of Salford, University of Surrey, University of Southampton and BBC R&D that aims to revisit the way people consume audio.