3D audio reproduction using frontal projection headphones

3D audio reproduction over headphones has become one of the most commonly used forms of playback system. Headphones provide a private listening space and are extremely convenient to use due to portability. However, headphones playback of 3D audio is marred by several challenges. Head related transfer functions (HRTFs) contain all the spatial information involved in the propagation of an acoustic wave from the source position to the receiver position. HRTFs encapsulate the spectral, temporal as well as timbral effects in the source sound spectrum that are caused due to the interaction of the source wave (diffraction, reflections, and scattering) with the human torso, shoulders, head and the pinna for any given source location. Human ears are highly idiosyncratic and thus, HRTFs are also unique and vary largely among different subjects. Use of non-individualized HRTFs degrade the 3D audio perception by introducing front-back confusions, up-down reversals, in-head localization (IHL) and timbral coloration. Therefore, individualized HRTFs are necessary to provide an accurate and immersive perception of 3D sound. However, measuring these individualized HRTFs are extremely tedious. HRTFs have to be measured precisely for every azimuth, elevation, and distance for every individual, which is practically not feasible. For distances in the near field (< 1 m), the measurement of individualized HRTFs is even more difficult due to the large variation of HRTFs with distances in the near-field. Thus, easier techniques to obtain the individualized HRTFs at any source location have to be developed. XXll ATTENTION: The Singapore Copyright Act applies to the use of this document. Nanyang Technological University Library