THE SUBWOOFER - BACKGROUND INFO
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The Subwoofer
A subwoofer is a monitor that reproduces low frequencies. The purpose is to take over from the main monitor(s) as
frequencies approach the lower end of the frequency range. I.e. approximately below 120 Hz. When used in professional
monitor systems it is commonly preferred to use subwoofers below approximately 80 Hz. But of course it depends on the
performance of the main monitors.
The low frequency contents of just one or all the main channels can be directed to one subwoofer.
From the psycho-acoustics we know that there is no directional information in audio signals below approximately 120 Hz.
Hence the advantage of placing the subwoofer in a position where the best distribution is achieved.
However it is very important that the distortion in the subwoofer is reduced to an absolute minimum because distortion
results in the production of harmonics (2, 3, 4 etc. times the frequency reproduced). Especially the third harmonic may
dominate. Reproducing a frequency of 100 Hz can result in the generating of an audible frequency component at 300 Hz,
which presents directional information to the human hearing system.
ΣΣ
Sub
L
C
R
Ls
Rs
Bass management
Bass management (sometimes called bass redirection) is a very important feature - and it is in general an absolute
necessity if you want to make a 5-channel set-up in a small room! There are several reasons for this.
The bass management system is designed to subtract the bass contents of all main channels and reproduce this by the
use of a sub woofer. The AIR-series provides a number of possible cross-over frequencies that can be determined by the
user.
Principal set-up for the bass management. It can be used
with any number of main monitors up to five.
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