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Front
Front
Right
Back
Right
Front
Left
Back
Left
Figure 1.9: BeoLab 90 has five beam di-
rections available, allowing you to opti-
mise for different listening positions.
1.1.3
ARC: Active Room
Compensation
In 2002, Bang & Olufsen introduced
the BeoLab 5 which included
ABC –
Automatic Bass Calibration
. This was a
system that used a microphone to
measure the effects of the listening
room’s acoustical behaviour on the
sound of the loudspeaker, and then
created a filter that compensated for
those effects in the low frequency
band. As a simple example, if your
room tended to increase the apparent
bass level, then the BeoLab 5’s would
reduce their bass level by the same
amount.
BeoLab 90 takes this concept to a new
level with its
Active Room
Compensation
or
ARC
. Using an
external microphone (available from
your Bang & Olufsen dealer), you can
measure the effects of your room’s
acoustical behaviour in different zones
in the room and subsequently select
optimised compensation filters for
different situations. For example, you
can customise a filter for the sofa, and
another for your dining area. In cases
where you are moving between these
locations, you can simply select a
combination of both filters to create a
single compensation filter that
improves the sound experience in both
locations.
The BeoLab 90 also offers another
development in acoustical room
compensation: multichannel
processing. This means that the
loudspeakers not only “see” each other
as having an effect on the room – but
they help each other to control the
room’s acoustical influence.
1.1.4
Performance
BeoLab 90 has been designed from the
outset to deliver an unparalleled audio
performance. Measured directly in
front of the loudspeaker, it has a
frequency range that exceeds the
limits of human hearing at normal
listening levels as can be seen in the
comparison plot in Figure
. (see
the
for more
details).
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