De-emphasis is a filtering circuit or process that restores the original spectral balance of an audio signal, correcting the changes previously made by pre-emphasis. This system works by attenuating high frequencies during the playback or reception stage of the signal.

Its operation is the inverse of pre-emphasis, which artificially boosts high frequencies before recording (as in vinyl records) or transmission (as in FM radio). By reducing these high frequencies back to their natural level, de-emphasis also drastically attenuates high-frequency background noise, such as hissing and interference, introduced by the transmission or storage medium, resulting in audio with correct tonality and a lower noise level.