CLIOwin 7 PCI User's Manual - Audiomatica

4.5.4 MICROPHONE CONTROL
Switches Channel A phantom power on and off. This 8.2V supply is needed to operate
Audiomatica's microphones MIC-01 and MIC-02.
Switches Channel B phantom power on and off.
Enters the Microphone Sensitivity dialog box.
Fig.4.5 Microphone sensitivity dialog
When taking acoustical measurements, the readings and the scales will be in Pascals
(Pa or dBSPL). In this case, the software will assume that you are measuring a pressure
quantity and it therefore needs to know a conversion factor that defines the voltage
produced by the microphone when it is measuring a certain pressure. This conversion
factor is usually the sensitivity of the microphone (as found in the microphone’s
calibration chart) or the sensitivity of the microphone + preamplifier chain of equipment.
When working with the CLIO system there are two possible cases:
a) you are using the microphone MIC-01 or MIC-02, so it is necessary to input the
sensitivity of the microphone (in mV/Pa).
b) you are using the PRE-01 preamplifier, it is necessary to know its internal gain; if
it is 0dB then input the microphone sensitivity, if it is +20dB then input the microphone
sensitivity multiplied by 10.
NOTE: It is necessary to input two separate sensitivities, one for channel A and one for
channel B. When the A-B balanced input configuration is selected (see 4.7.1) the
software will use the channel A sensitivity.
Please also refer to 8.4.1 for a description of the procedure for assessing the
sensitivity of the microphonic chain using an acoustic calibrator capable of
producing 94dBSPL.
By checking the Microphone Correction check boxes the software will correct the
measured curve according to the data stored in the “MICA.CAL” and “MICB.CAL” files;
one for each input channel.
The example below shows a sample text file created to store the microphone frequency
response:
Freq dB Phase
1000 0 0
4000 0.25 0
8000 0.33 0
10000 0.5 0
15000 1.75 0
20000 2.5 0
42 Chapter 4 - CLIOwin basics