Figure 1.

Directional filtering properties of the cat’s outer ear. A. Head-related transfer functions (HRTFs) at five elevations in the median vertical plane (numerical labels indicate elevation) and one lateralized location in the interaural horizontal plane (dashed line). B. A larger collection of HRTFs for locations encompassing the frontal sound field. Bold lines in A and B indicate the average spectrum of all HRTFs. These recording were originally reported by Rice et al., 1992.