Audioscan Verifit - Manual (Page 42)

Verifit ® User's Guide Version 3.12  May 2015
Calibration check for coupler microphone
Accuracy of test box measurements depends on the calibration of the coupler microphone. This should be
checked regularly using a microphone calibrator with an adapter ring. The RE780 (1 1/8 in.) and RE781 (1in.)
rings are designed for Quest CA22 and QC-10/20 respectively. To verify the coupler microphone calibration:
1. Calibrate the test box reference microphone. See Calibrating test box reference microphone
2. Screw the appropriate calibrator ring onto the coupler microphone.
3. Insert the coupler microphone with the attached calibrator ring into the calibrator opening.
4. Turn the calibrator on and adjust it to present one of the available frequencies and levels (e.g., 94 dB SPL at
1000 Hz).
5. Press , then highlight and [Test box measures], then highlight and [Manual
control].
6. Highlight and the [Level] window, then highlight and 0 from the drop-down list.
7. Highlight, then the [Frequency] window, then highlight and the frequency of the calibrator
(e.g. 1000 Hz) from the drop-down list.
8. Highlight, then the [Filter] window, then highlight and 1/12th octave from the drop-down
list.
42