Effect of spatial audio processing on attention redirection and speech intelligibility in multi-talker communication

Most current communication systems for mission critical applications use devices with relatively simple audio presentation to the user, employing single channel communication. An increasing number of applications are requiring users to monitor and listen to multiple talkers concurrently. This paper describes results of an experiment investigating the differences in performance in a transcription task when listeners were listening to multi-talker communication using two different Head-Related Transfer Functions (HRTF) data sets in comparison to monaural listening. The goal of this research is two-fold: 1) to assess the impact on attention redirection and the accuracy of the NATO phonetic word transcription based on the pre-selected HRTFs used, as compared to a diotic presentation, as the number of talkers increases; 2) to investigate whether there is a difference in performance between younger and older listeners. Results indicate a significant improvement when using spatial audio, in the accuracy of the transcription and number of missed characters, especially for participants in the older age group.