code: def _set_frequency_spacing(self, min_freq, max_freq):
          
  
          self.frequency_spacing = np.linspace(min_freq, max_freq, num=self._sheet_dimensions[0]+1, endpoint=True)
docs: Frequency spacing to use, i.e. how to map the available
          frequency range to the discrete sheet rows.
  
          NOTE: We're calculating the spacing of a range between the
          highest and lowest frequencies, the actual segmentation and
          averaging of the frequencies to fit this spacing occurs in
          _getAmplitudes().
  
          This method is here solely to provide a minimal overload if
          custom spacing is required.