July 4, 2008
When talking to people about 5.1 audio, one of the more common problems in helping people understand certain concepts, is the confusion involving some of the basic terminology.
What is the .1 / LFE Channel and why does it exist?
The .1 or LFE is a channel which is exclusively used for frequencies below 120Hz (below 80Hz for DTS). It is therefore a bandwidth limited channel, but it is not the same as the subwoofer, which is the speaker that typically reproduces the LFE channel in a home audio or studio monitoring system (more information is provided below). The purpose of this channel is to provide an additional 10dB of electrical headroom, for low frequencies, above the main channels. This is done by calibrating the acoustic playback level, so that it has 10dB of in-band gain above the other channels (fronts and surrounds).