How do I apply a bandpass filter on an audio file which is in wav format? And write back the filtered data in a new wav file for further analysis.
Consider looking at this StackOverflow answer which provides the full code for creating a Butterworth bandpass filter. In the sample code the answerer provides, the filter is applied to a manually constructed simplistic signal
x. If you substitute this signal with your own NumPy array, it should achieve the intended effect.