LFE

Abbreviation for Low Frequency Effects, a term used in surround sound mixing. Low-frequency effects are mixed to a separate so-called LFE channel in modern movie sound production. The LFE channel carries non-essential effects enhancement – such as the low-frequency component of an explosion – often at higher levels than the other channels. The idea behind a separate LFE channel is to provide the extra low-frequency headroom needed to put low-frequency signal components on equal psychoacoustic footing with midrange signal components which require less energy for the same perceived loudness.