input file : source soundfile
output file : destination soundfile (when marked)
or result.wav (for unregistered files)
processing mode : local or global
The bandpass filter can be used to remove both the low-frequency and high-frequency components of the signal. The filter has three adjustable parameters.
The lower and higher cutoff frequencies (expressed in hertz) determine the passband of the filter, i.e. the frequency range [lower cutoff frequency,higher cutoff frequency] in which the signal is (almost) not modified. Both cutoff frequencies have to remain in the range [20 Hz , 0.45(sampling frequency)]
The stopband attenuation coefficient (expressed in decibels per octave) decides upon the 'sharpness' of the filter - the larger the value of this coefficient, the steeper become 'cuts' at both cutoff frequencies. Sharper filters are more complex, and hence they result in longer processing times.