Perceptually Optimised Sound Zones (POSZ)
Dates
Start date: 1 October 2010
End date: 31 December 2013
Summary
Often, two people in a single room want to listen to different items of audio. It may be that one person wants to watch television whilst the other wants to listen to the radio, or even that one wants to play a computer game whilst the other reads in silence. The obvious solution to this would be for all individuals to wear headphones, however this dramatically increases isolation (not just in acoustic terms), is impractical when multiple people want to listen to one or other of the audio streams, and could be uncomfortable over an extended period.
Details
The aim, therefore, is to be able to reproduce sounds solely within confined areas of an acoustical space, in other words to reproduce specific sound zones whilst minimising crosstalk with other zones. An example is shown below of a living room containing two sound zones, A and B, with the remaining space being either a quiet area, or an area where the reproduced sound is relatively unimportant.
A number of previous studies have examined methods to reproduce multiple sound zones. However, these have exclusively judged the performance by using level-based metrics such as signal to noise or signal to interferer ratios. Unfortunately, this gives little indication of the perceived quality of the system, or whether the result will be acceptable to a consumer.
The key difference of this project is the combination of engineering and psychoacoustics.
The engineering research is being conducted by staff and students from the Centre for Vision, Speech and Signal Processing in the Department of Electronic Engineering. They are developing methods to radiate sound so that the audio is concentrated on the corresponding sound zones, with minimal spill into other zones.
The psychoacoustic research is being conducted by staff and students from the Institute of Sound Recording. They are developing a model of the perceived effect of interfering signals in a sound zone, in order to either quantify the performance of a system in a perceptually-relevant way.
For more information, please follow the links below.
Engineering:
- Phil Coleman
- Marek Olik
Psychoacoustics:
Publications
- Coleman, P., Moller, M., Olsen, M., Olik, M., Jackson, P.J.B., Pedersen, J.A., 2012: 'Performance of optimized sound field control techniques in simulated and real acoustic environments', Journal of the Acoustical Society of America, vol. 131, no. 4, pp. 3465.
- Francombe, J., Mason, R., Dewhirst, M. and Bech, S. 2012: 'Determining the threshold of acceptability for an interfering audio programme', 132nd Audio Engineering Society Convention, preprint 8639.