pitch correction

Pitch correction is an electronic effects unit or audio software that changes the intonation (highness or lowness in pitch) of an audio signal so that all pitches will be notes from the equally tempered system (i.e., like the pitches on a piano). Pitch correction devices do this without affecting other aspects of its sound. Pitch correction first detects the pitch of an audio signal (using a live pitch detection algorithm), then calculates the desired change and modifies the audio signal accordingly. The widest use of pitch corrector devices is in Western popular music on vocal lines.