Audioscan Verifit - Manual (Page 64)

Verifit ® User's Guide Version 3.12  May 2015
process compares this response with the flat, factory-calibrated response of the on-ear reference microphone and
compensates all subsequent probe-tube measurements for this difference. It may be performed as often as
desired but will be invalidated at 12 am the following day or at 12 am the following Monday, depending on the
choice of Daily or Weekly calibration interval. After the calibration has expired, you will be prompted to
calibrate whenever you attempt a test that uses the on-ear measurement microphones.
It is suggested that a copy of the calibration curves for the probe modules when new be posted near the Verifit
for comparison with daily or weekly curves. If there is a drift in calibration with time, the module may need
replacement. See Calibration check for probe module.
Calibration should be repeated if a probe module is replaced or if a probe-tube with different dimensions is
installed.
Switching left and right probe modules after calibration will result in the wrong calibration curve being applied.
Calibration of on-ear probe microphone
Ensure the probe microphone assembly to be calibrated is plugged into the appropriate jack. See Microphone
connection and On-ear calibration facts
1. Press <Tests>, then highlight & <PICK> [On-ear measures], then highlight & <PICK> [Calibration].
2. Press the enlarged end of a probe tube as far as it will go, into the recessed opening at the top of the probe
module.
3. Position the open end of the probe tube in front of the reference microphone inlet and press it between the
posts as shown.
4. Hold the probe module 15 - 90 cm (6 – 36 inches) away from and directly in front of the sound-field
loudspeaker. Orientation of the probe module is not critical.
5. Press <PICK> to calibrate. The resulting curve should be similar in shape to that shown but may be shifted
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