5.3
Calibration
5.3.1
How often is calibration necessary?
Otometrics recommends that you set up a schedule for fully testing and calibrating the AURICAL HIT microphones at reg-
ular intervals. This will help meet standards, and will ensure continued reliability and accuracy.
Reference microphone
Otometrics recommends that you calibrate the reference microphone daily or weekly. Set up the interval to suit your pur-
poses. See
Calibrating the reference microphone
.
Coupler microphone
Otometrics recommends that a qualified service technician calibrates and validates the coupler microphone at least once a
year. See
Calibrating the coupler microphone
. OTOsuite will prompt you with an indication of when the calibration
expires.
5.3.2
Environment Report
The Environment Report is a troubleshooting/system self-test tool, which can be used for verifying that the microphones,
loudspeakers, internal electronics and the acoustic chamber are functioning properly.
Note
•
Make sure that you follow the on-screen instructions carefully to obtain correct results.
The tool executes the following measurements in an automatic sequence:
•
90 dB front speaker frequency sweep
•
70 dB back speaker frequency sweep
•
Background noise
Both reference microphone and coupler microphone are used in each of these measurements, and the results are com-
pared between them.
Procedure
1. Make sure that the test environment is as silent as possible.
2. Place the coupler in the high position.
3. Position the reference microphone (1) pointing straight down from above and
centered 1-2 millimeters above the coupler measurement microphone (3).
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Otometrics - AURICAL HIT
5 Cleaning, Repair and Calibration
