Simple Explanation

The special sound effects track in movies that carries the deep bass—like explosions or rumbles—played through a subwoofer.

Concise Technical Definition

A dedicated, bandwidth-limited (.1) audio channel (typically 20 Hz–120 Hz) used in multichannel formats like 5.1 or 7.1 to carry low-frequency effects.

Layman-Friendly Analogy

Like having a separate sound pipe just for thunder and explosions that you feel in your chest.

Industry Usage Summary

In multichannel audio formats (Dolby Digital, DTS, Atmos), the LFE channel is encoded separately to enhance cinematic impact. It’s routed to the subwoofer via AV receivers’ bass management systems and is distinct from redirected bass from other channels.

Engineering Shortcut

".1" effects-only bass channel, 20 Hz–120 Hz; routed to sub.

Full Technical Explanation

The LFE (Low Frequency Effects) channel is a specialized, bandwidth-limited channel in multichannel surround sound formats (like 5.1, 7.1, or Atmos). It is dedicated to reproducing deep, low-frequency content—typically between 20 Hz and 120 Hz—used to enhance dramatic moments (e.g., explosions, earthquakes). This is the ".1" in "5.1" and refers not to a speaker count but to 1/10th the bandwidth of full-range channels. Audio/video processors send this channel’s content directly to the subwoofer, though additional low-frequency information from other channels may also be routed there depending on the bass management and speaker size settings (e.g., if speakers are set to “small”). The LFE is not the same as redirected bass—it is a distinct channel created during the mixing process to "sweeten" the low end of effects or scenes.