Princeton University  

Multiple 3D Audio Sweet Spots


By combining the phased array (aka Digital Sound Projector™) technology of Cambridge Mechatronics Ltd. (CML) with Princeton's BACCH™ 3D Sound technology, researchers at the 3D3A Lab were able to produce multiple sweet spots, where multiple listeners can sit and experience the same accurate 3D sound image.

CML's phased array speakers (aka Digital Sound Projectors™) can form sound beams and direct them to the ears of multiple listeners. The stereo signal for each pair of sound beams is digitally processed in real time using Princeton's BACCH™ Filters to produce an independent 3D audio sweet spot for each listener. The first demostration was for two sweet spots and was achieved on January 25th, 2011 at the 3D3A Lab.

Since the beams are directed at the listeners, there is minimal interaction with the walls of the listening room and hence minimal degradation of crosstalk cacncellation levels from those achieved in anechoic environments.

This breakthough opens the door for applications of the BACCH™ 3D Sound technology in 3D TVs and 3D cinema where the requirement of having multiple listeners is essential.

The combination of the two technologies has been been branded DynaSonix™ and has been further enhanced by the addition of miniature Camera-Based Automatic Set-Up (CBAS™) developed by CML. A Flat Panel TV sound system using DynaSonix™ will be able to locate up to eight listeners in a room and then direct a pair of sound beams to each listener, one beam for the left ear and the other for the right. Thanks to the effectiveness of Princeton’s novel BACCH™ Filter technology, the left ear and right ear hear two related but different sets of audio content. This allows for the delivery of a true 3D audio experience, designed to complement the fast growing deployment of 3D Televisions.

For more on DynaSonix™, read this press release from CML. For more on the integration of 3D audio with 3D TV, visit this webpage.