This mesh plot shows the frequency response for KEMAR's right ear as
the source moves in the horizontal plane. Although this surface is rather
bumpy, if you look at any one frequency you can see a roughly sinusoidal
change with azimuth. As expected, the response is usually greatest when
the source is at 90° and directed into the right ear, and weakest when
the source is at 270° on the opposite side of the head.
Once again, front/back (0° and 180°) responses are quite similar.
The graph below shows that the front response is a few dB higher than the
back response in the frequency range from around 4 to 7 kHz. The peak around
4 kHz is due to ear-canal resonance. The notch around 10
kHz that is also clearly visible in the surface plot above is the famous
"pinna notch",
whose frequency changes with elevation.
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