Note that Frequency Tilt can have
different settings for different Presets.
The range of the controller is from -6.0
dB to +6.0 dB in steps of 0.5 dB. As
can be seen in Figure
, a controller
setting of +6.0 will result in a
peak-to-peak magnitude response
deviation of approximately 6 dB,
however the maximum deviation from
a flat response is only 3 dB.
10
100
1,000
10,000
−4
−3
−2
−1
0
1
2
3
4
Frequency (Hz)
Gain (dB)
Figure 5.39:
Magnitude Responses, Fre-
quency Tilt controller. Note that this fil-
ter is applied to both loudspeakers si-
multaneously. Black curves show the re-
sult for positive slider values, red curves
show negative slider values.
5.10.4
Sound Enhance
The Sound Enhance setting is similar to
the Frequency Tilt setting in that it
affects the low and high frequency
bands with a single slider. Increasing
the Sound Enhance value will increase
the level of the bass and treble bands
while reducing the midrange.
Decreasing the Sound Enhance value
will have the opposite effect and will
enhance the midrange.
The Sound Enhance setting will have
no effect on this audio signal at its
middle setting.
Note that Sound Enhance can have
different settings for different Presets.
The range of the controller is from -6.0
dB to +6.0 dB in steps of 0.5 dB. As
can be seen in Figure
, a controller
setting of +6.0 will result in a
peak-to-peak magnitude response
deviation of approximately 6 dB,
however the maximum deviation from
a flat response is only 3 dB.
10
100
1,000
10,000
−4
−3
−2
−1
0
1
2
3
4
Frequency (Hz)
Gain (dB)
Figure 5.40:
Magnitude Responses,
Sound Enhance controller.
Note that
this filter is applied to both loudspeak-
ers simultaneously. Black curves show
the result for positive slider values, red
curves show negative slider values.
5.10.5
Sound Design
At the end of the development process,
all Bang & Olufsen loudspeakers go
through a final tuning process where
the loudspeaker’s timbre is evaluated
in different listening environments. In
order to achieve an optimised balance
between the on-axis frequency
response and the three-dimensional
“power response”, filters are included
in the signal path to give the
loudspeaker a final
sound design
.
The BeoLab 90 is no exception to this –
as a result, it has a custom-tuned,
factory-default sound design for every
combination of beam widths, beam
directions, and latency modes.
However, there may be some specific
cases where this tuning is not
applicable. One example of this is a
case where the BeoLab 90 is used in a
listening room such as a recording
studio where acoustical absorption has
been applied to the various surfaces.
In this case, it may be preferable to
use the BeoLab 90 as a “studio
monitor” style of loudspeaker, where
the overall tuning is designed to
deliver a flat magnitude response
when measured on-axis to the
loudspeaker in a free field.
The
Sound Design
control allows you to
switch between these two tunings. It is
currently planned that additional sound
designs will be made available in
future software releases.
5.10.6
Parametric Equaliser
For a general introduction to
equalisation, please see
Introduction to Parametric Equalisers
In cases where a more detailed control
of the frequency response of the
loudspeaker is needed, a 10-band
parametric equaliser is available. This
allows you to sculpt the timbral
balance of the loudspeaker with a high
degree of precision.
When the gains of all ten filters in the
Parametric Equaliser are set to 0 dB,
the processing block is automatically
disabled.
Figure
is given as a rough “map”
of frequency as reference when using
the Parametric Equaliser. Additional
guidance is given in Table
on page
440.0 Hz
660.0 Hz
880.0 Hz
1320.0 Hz
220.0 Hz
261.6 Hz
330.0 Hz
110.0 Hz
165.0 Hz
55.0 Hz
55.0 Hz
Figure 5.41: Pitch vs.
Fundamental
frequency for reference purposes when
equalising.
The Parametric EQ consists of one
low-shelving filter, one high-shelving
filter, and 8 reciprocal peak-dip (or
peaking) filters, each with a variable
Frequency, Gain, and Q.
The filters’ frequency ranges are listed
in Table
on page
and are limited
to ISO 1/6th octave centres. For more
information, please refer to Table
on page
The available Q’s of the filters are
limited to the values listed in Table
on page
Note that all filters are implemented in
series, and that frequencies may be
overlapped in cases where additional
gain is desired.
24
