Directional Properties of the Dummy-Head in Measurement Techniques based on Binaural Evaluation

Dummy-heads are often used for standardized measurements where modeling of the average human head and torso is relevant and evaluation of results is made binaurally. They are used for noise measurements, in-situ testing of acoustical environments as well as for research in human spatial hearing and localization. As a measurement device, it has spectral, temporal and first of all, directional properties. These are characterized by the complex Head-Related Transfer Functions (HRTF) describing the directional dependent filtering of the ears. These properties can be evaluated through measurements using accurate settings of sound source directions, long-term averaging and increased spatial resolution. Monaural HRTFs of a Brüel & Kjær manikin were measured in the anechoic chamber and they were evaluated spectrally by focusing on directional properties, spectral distortions, effect of the head-shadow area and symmetries in measurement data.