Creating the Sydney York Morphological and Acoustic Recordings of Ears Database

Abstract

This paper introduces the process for creating the Sydney York Morphological and Acoustic Recordings of Ears (SYMARE) database. The SYMARE database supports research exploring the relationship between the morphology of human outer ears and their acoustic filtering properties-a relationship that is viewed by many as holding the key to human spatial hearing and the future of 3D personal audio. The SYMARE database is comprised of acoustically measured head-related impulse responses for 61 listeners (48 male/13 female), multiple high-resolution surface mesh models (upper torso, head and ears) for these listeners obtained from magnetic resonance imaging (MRI) data, and the corresponding simulated HRIR data for these listeners generated using the Fast Multipole Boundary Element Method (FM-BEM). In this work, we compare acoustically measured HRIR data for 61 listeners with the listeners' corresponding simulated HRIR data generated using the FM-BEM.Index Terms-Fast multipole boundary element method, head-related transfer function, morphological data, virtual auditory space, 3D audio, 3D mesh models. Manuscript

A framework for geometry acquisition, 3-D printing, simulation, and measurement of head-related transfer functions with a focus on hearing-assistive devices

“…6 shows the spatial correlation coefficients for both left and right ear, and the same conditions as those for the analysis based on spectral distortions. The repetition of the acoustic measurement yielded correlation coefficients larger than 0.9 for most of the frequencies, which is in agreement with most of the results from [23]. In contrast, the correlation coefficients representing the similarity between the human and simulated HRTFs were much lower, indicating not much similarity between the simulation and acoustic measurements.…”

“…Also note that the model from [4], while showing good predictive power for normal-hearing listeners, was not applied in our study because it has neither been calibrated nor applied to hearingimpaired listeners yet. Finally, pairs of conditions were compared by means of the spatial correlation analysis [23]. For each condition, spectral magnitudes were calculated for a single frequency band and considered for all spatial positions.…”

“…As an alternative to demanding acoustic measurements, HRTF can also be numerically calculated from a three-dimensional (3D) representation of a human geometry [20][21][22][23] and established methods have shown good congruence between measured and simulated HRTFs for frequencies below 7 kHz [23,24].…”

The Wave-Matching Boundary Integral Equation — An energy approach to Galerkin BEM for acoustic wave propagation problems

“…Despite the advantages of BEM -more straightforward meshing, a reduction in the number of degrees of freedom relative to methods that discretise the quantities in the volume and ease of modelling unbounded problems -its use in acoustic engineering has mostly been in a small set of specific cases. These include, for example: prediction and optimisation of the sound scattering properties of acoustic objects and treatments [1,2] and noise barriers [3,4]; estimation of headrelated transfer functions from head geometry [5,6].…”

Computing interaural differences through finite element modeling of idealized human heads

“…This structure is highly individualistic and leads to useful information about the elevation of a source of sound, including differences between a source in front of the listener and a source in back (Roffler and Butler, 1968;Blauert, 1983). This frequency region has been the focus of several computational efforts with special interest in individual pinnae (Gumerov et al, 2010;Mokhtari et al, 2011;Jin et al, 2014). (2) There is also a frequency dependence well below 4000 Hz that depends less on individual differences because longer wavelengths are less sensitive to individual anatomical details.…”