FIG. 12.

Estimation of the ideal open-cavity umbo response H _io (blue) based on the measurement with the smallest size of cavity-wall opening H _po (red) in gerbil J. An RFP frequency response H _f (green) is fitted to the measured response in the frequency range indicated by the two parallel orange lines. From this fitted frequency response, the complex conjugate pair of zeroes at the central frequency of the opening feature (marked with an arrow and open circle) and the complex conjugate pair of poles at a slightly higher frequency (marked with an arrow and a cross) were taken to form H _o (solid black). The dashed black line is what would result if H _o included only the complex conjugate pair of zeroes.