Localization in the anechoic environment and with virtual acoustical directional
presentation investigated with a laser-pointing method 

Bernhard U. Seeber 
AG Technische Akustik, MMK, Munich Univ. of Technology, Arcisstr. 21, D-80290
Munich, Germany 

Many scientific studies investigate the acoustical localization in the field of
vision. Hence it is suitable to display the perceived auditory direction by a
light point. In formerly known methods subjects use a hand-held light pointer or
a pivoted pointer in front of them. However, the subject\u2019s motor system or
the optical parallax may influence the results of those techniques. Instead, the
newly proposed method utilizes a laser pointer with a deflection unit. Subjects
enter the perceived direction with a trackball. The laser spot moves according to
the rotation of the ball smoothly on a defined track. Localization results
obtained by this method are presented. The reproduction of the acoustical
direction was varied in three ways: free-field, headphones using individual
HRTFs, and headphones using selected non-individual HRTFs. Furthermore, the
influence of the initial laser spot position is investigated. The intuitive
experimental operation and the high resolution of the laser-pointer method make
it particularly suitable for localization research in audiology, psychoacoustics,
and virtual acoustics.