Last month the last paper from work done during my thesis was published in the Journal of the Audio Engineering Society. We tested localisation for off-centre listeners with third order Ambisonics for two different noise signals: transient and non-transient. We found, in line with Precedence Effect literature, that the transient signal produced sound images pulled more towards the nearer loudspeakers than the non-transient signal.
We also tested different localisation models. All of them were relatively good at predicting the perceptual results. The best results were obtained by an extended version of Gerzon’s energy vector that includes elements of localisation dominances and the precedence effect (See here for an overview and here for the paper).
P. Stitt, S. Bertet, and M. van Walstijn, “Off-Centre Listening with Third-Order Ambisonics: Dependence of Perceived Source Direction on Signal Type,” J. Audio Eng. Soc., vol. 65, no. 3, pp. 118–197, 2017.
Links: DOI – ResearchGate
Last month we had a paper published in the Journal of the Acoustical Society of America (JASA) on the influence of large head movements with head-tracked binaural when using non-individual HRTFs. In brief, we found that large head movements helped improve localisation for frontal and rear sources, had little impact on lateral sources and that micro head movements didn’t seem to produce increased externalisation. You can get a lot more detail (even individual subject results) from the paper itself!
The work was lead by Etienne Hendrickx and was a collaboration as part of the BiLi Project. In this case the partners were LIMSI-CNRS (during my post-doc) and the Conservatoire de Paris (CNSMdP).
E. Hendrickx, P. Stitt, J.-C. Messonnier, J.-M. Lyzwa, B. F. Katz, and C. de Boishéraud, “Influence of head tracking on the externalization of speech stimuli for non-individualized binaural synthesis,” J. Acoust. Soc. Am., vol. 141, no. 3, pp. 2011–2023, 2017.
Links: DOI – ResearchGate
Today I’m finishing up my first listening experiment for my PhD. It tested two different Ambisonic systems for different conditions to compare their robustness for localisation.
I have to say, I haven’t gone through the results in detail but the comments from the participants have been incredibly useful and illuminating.
I still have to make my way through mountains of results but just from the feedback I feel like I’ve really learned so much about how people perceive the systems.
Now I just need to brush up on my statistics for the analysis!