Bass Management Theory - KRK Systems 12sHO Guide D'utilisation

Beyond Stereo to 5.1 Surround
When using a subwoofer for the LFE (Low Frequency Effects) channel in a 5.1 surround monitoring
system, rotate the low pass filter all the way to the right to the 170Hz position. Note that the LFE channel
is set with an additional 10dB of monitoring gain. To set this level, we recommend using 2-octave wide,
band-passed, pink noise from 20 to 80Hz for the LFE channel and 500 to 2,000Hz for the near-field
speakers. After adjusting each near-field monitor one at a time to 85dB SPL, adjust the LFE channel 10dB
louder to 95dB SPL.

Bass Management Theory

Bass management is a method for extending the bass response of small, near-field speakers used in 5.1
surrounds sound systems (familiarly called home-theatre systems). This is done by routing frequencies
below a cutoff point to a separate subwoofer (sometimes called "bass redirection" in home-theater
receivers). This can usually be enabled by selecting "Small Speakers" from a speaker set up menu. This
process places a group of two-way filters in the speaker output path, typically at 80Hz. These filters route
all sonic energy above this given frequency (e.g. 80Hz) to the Left, Center, Right, Left Surround and Right
Surround speakers. In turn, the process redirects the low-frequency energy from the five full-range
channels to a single subwoofer, which also reproduces the separate LFE channel.
Bass management is used in practically every consumer home-theater system. Therefore, audio engineers
mixing for modern listeners should realize that their studio monitoring systems must be able to reproduce
sufficient low frequencies so they can avoid recording undesirable subsonic information. Without such
studio monitoring, it is possible to release a mix with infrasonic problems, such as pops, air conditioner
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