Roland VM-C7100 Owner's Manual page 189

Chapter 9 Using the Spectrum Analyzer
6. Use [V2] to set the analyzer source to the input channel to which you
connected the microphone.
7. The microphone captures the sound of the pink noise in the hall, and this is
displayed on the VIEW page.
The graph shows the frequency characteristics of the concert hall.
For a relatively small room, such as a meeting room, you can use your own voice and
a microphone instead of pink noise. Connect the microphone to one of the inputs and
speak into it. By changing the tone of your voice and watching the display, you can
detect, the point at which unwanted room resonation occurs.
Correcting acoustic problems using an equalizer
Press [PAGE UP] or [PAGE DOWN] from the ANALYZER to display the MAIN EQ
page.
fig.09-07
The MAIN EQ page opens only under the following conditions:
• A pair of effects (1 to 8) are set up as insert effects for the MAIN OUT.
• The 31-band graphic equalizer is selected as the effect algorithm.
• The selected effects are enabled as the FX UNIT FOR ANALYZER on the
analyzer's SETUP page.
This page allows you to monitor and correct frequency problems using the 31-band
graphic equalizer together with the analyzer. When correcting problems in a sound-
reinforcement (SR) site, such as the concert hall described above, you can use the
equalizer in the lower section of the screen to flatten the site's frequency-
reproduction characteristics while viewing the analyzer in the upper section of the
screen.
The following operations are available on this screen:
• Analyzer level
+63 dB, you can raise or lower the vertical scaling of displayed frequency levels
to improve visibility.
• Pause Press [F1] (PAUSE) to freeze the graphic display, allowing you to
scrutinize a moment in time at your leisure. Press [F1] again to release the
display back to normal operation.
• Bass cut This filter cuts the level of any frequencies below a specified
frequency. Press [F2] (BASSCUT) to turn this feature on and turn [V2] (FREQ) to
set the threshold frequency.
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By turning the V1 knob (ANALYZER LEVEL) from -64 dB to
It's recommended that you
to use a commercially
available monaural
microphone designed
especially for the
measurement of frequency
characteristics. A Roland
DR-20 general-purpose
dynamic microphone can
also be used for this
purpose. If you use a DR-
20, press [PAGE UP] or
[PAGE DOWN] to display
the SETUP page, and use
[V1] to set CURVE ADJUST
in the middle of the screen
to MIC DR-20. Press [F1] to
confirm your selection.
The analyzer and equalizer
together use two pairs of
effects (e.g. Effects 1 and 2
for the equalizer and
Effects 3 and 4 for the
analyzer). Therefore, this
procedure requires the
installation of least one
VS8F-2 Effect Expansion
Board.