MRC EQ Limit, Руководство пользователя

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MRC AUDIO EQ
Limit
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7.4.1 Calibration process
Before executing the calibration process it is necessary to configure the global limiting level as
described in previous chapters. It is also necessary that the sound system, the limiter and its
sensing microphone (must be microphone 1 for calibration), are installed at their final locations.
The first step is to verify that the microphone level shown at the SCL application is the same
as the level shown by a certified sound level meter, to compensate for the variations introduced
by different factors like the distance to the speakers, the sensing microphone’s proximity to the
ceiling or walls, the effects of the sensing microphone’s protecting box, etc.
To do so, first select the measuring filter and the measure mode to be equal at both limiter and
sound meter; click on the
Noise pink button to switch on the pink noise generator and have
pink noise sound in the house, and adjust the microphone 1 gain, G. MIC 1 slider, until both
limiter and sound meter measure the same level. Once adjusted microphone 1’s gain, click on
the
Noise button again to switch off the noise generator.
In the
G. MIC 1 slider control, the 0 point is adjusted at factory. This control can be adjusted
my moving the red slider with the mouse, by clicking on the top and/or bottom small red arrows
to obtain a 0.1dB increment per click, by typing a numeric value directly into the numeric box
at the bottom or by clicking on the numeric box up and own arrows to also obtain 0.1dB
increments.
The same adjustment can be done with microphone 2 if present.
Once the limiter’s sensing microphone measures the same as the sound level meter, you can
proceed to calibrate the whole sound system. During this process, pink noise will be emitted
through the sound system; avoid emitting any other sound in the house, be silent during this
process. The process is automatic and is guided by the top left corner LEDs and different
emerging windows; follow instructions:

At the Display box select slow.

Click on the CAL button. An emerging window appears inviting to fade out music and
turning the amplifiers to maximum power.

Click on the OK button. The limiter automatically turns its global gain to minimum,
activates pink noise and switches to “A” filters.

The Adjusting Global Gain LED starts to flash and the limiter automatically increases
the noise level until the sensing microphone reaches the limiting level.

Once reached, the Adjusting Global Gain LED stops flashing and the Balancing
Levels LED starts to flash. At this time the limiter is automatically adjusting the Line out
gain to match the microphone 1 level.

Once matched, the Balancing Levels LED stops flashing and the Calibrating Bands
LED starts flashing. The limiter registers the frequency band levels for later comparison,
taking around 30 seconds.

Choose Limiting Signal LED starts flashing. At this time choose the limiting signal:
microphone 1, SML or Line Out, by clicking on either the Limiting Signal: MIC1,SML
box or L.OUT box, located just underneath the meter bars.

Once chosen the limiting signal, all LEDs stop flashing and the pink noise is switched
off.