In FoxP2 hum mice, the calls had a lower start peak frequency with lower mean, minimum and maximum peak frequencies (Fig. 2c).
Some of these LDC species have been reported to change the frequency of maximum energy (peak frequency, PF) of their echolocation calls when they encounter a conspecific using the same or similar PF (Obrist, 1995; Ratcliffe et al., 2004; Bartonička et al., 2007; Surlykke and Moss, 2000).
In addition, there were significant differences in the location of the maximum of the peak frequency and in the location where pitch jumps occur (Fig. 2d).
Finally in an attempt to optimism the number of signals to be sensed, a variable error margin for the estimate of power, based on the ratio of the sound power at each frequency to the maximum peak in the considered frequency range is proposed and analyzed.
It is worth noting that there are three frequencies for which there is a maximum peak of dependence (resonance frequencies); at frequencies higher than 14 Hz, the dependence is not significant (indicating the decoupling zone).
For each syllable we measured minimum frequency of syllable, maximum frequency of syllable, peak frequency at the start point, end point, and time point of maximum amplitude of the syllable (annotated in Figure 1c).
The power spectrum is computed and its radial average is determined only around its maximum peak within a certain frequency range.
Typically, resonance frequency (f_{0}) and quality-factor Q can be extracted by a simple peak search and a numerical direct extraction of the quality-factor from a ratio of band-width at half maximum peak value and resonance frequency.
It is proved that a serial R L circuit can control the peak frequency, maximum and bandwidth of the sound absorption coefficient and the combining R L circuits shunted to multiple layers can control the sound absorption coefficients at multiple frequencies.
