A band-pass filter is an electronic device that allows signals within a specific frequency range to pass through while blocking signals outside that range. It is commonly used in audio processing, telecommunications, and radio broadcasting to isolate desired frequencies and reduce noise. The filter is characterized by its lower cutoff frequency and upper cutoff frequency, defining the bandwidth of frequencies that can pass. For example, in a radio receiver, a band-pass filter can help tune into a specific station by filtering out unwanted frequencies, ensuring clearer sound quality and better reception.