A parametric equalizer is an audio processing tool that allows users to adjust the frequency response of a sound. It provides control over specific frequency bands, enabling adjustments to the gain, bandwidth, and center frequency. This flexibility helps in enhancing or reducing certain sounds, making it popular in music production and live sound settings. Typically found in digital audio workstations and mixing consoles, parametric equalizers can improve audio clarity and balance. By targeting specific frequencies, users can eliminate unwanted noise or emphasize particular instruments, contributing to a more polished final mix. They are essential for achieving professional sound quality in various audio applications.