What is a high-pass filter?

A high-pass filter is designed to allow signals that are above a certain frequency to pass through while attenuating signals that fall below that frequency. This characteristic is important in a variety of applications, such as audio processing, where it may be used to eliminate low-frequency noise or hum.

In terms of functionality, the high-pass filter effectively sets a threshold frequency, known as the cutoff frequency. Signals with frequencies higher than this threshold can pass through unimpeded, while those with lower frequencies are reduced in amplitude or completely blocked, depending on the steepness of the filter's roll-off. This selective transmission is crucial for isolating specific frequency ranges for analysis or utilization in audio, communication systems, and other electronic applications.