This variable-frequency, audio bandpass filter is built around two 741 op amps that are connected in cascade. Two 741 op amps are configured as identical RC active filters and are connected in cascade for better selectivity. The filter`s tuning range is from 500~Hz to 1500 Hz. The overall voltage gain is slightly greater than 1 and the filter`s is about 5, The circuit can handle input signals of 4 V peak-to-peak without being overdriven. The circuit`s input impedance is over 200 kohm.