Calibration 201
11. Look at the response. This curve represents the difference between the
probe response and the reference response. The maximum deviation from
the zero line should be 5 dB.
12. If there is more than a 5 dB deviation from the zero line at any point along
the curve, the probe microphone is out of calibration.
C. Calibrating the Microphones
To enter the Microphone Calibration Screen:
1. Press [MENU] from Opening Screen
2. Press [F3] to enter Calibration Screen
3. Press [F3] to enter Microphone Calibration Screen.
To restore factory calibration:
1. Press [F1] to erase current calibration.
2. Press [F3] to restore factory calibration.
3. Press [F5] to store calibration.
Warning: If you press [F1], you must either restore the factory calibration, or
you must use a custom calibration. If you do not do one or the other, your
microphones will not be calibrated and your test results will be false.
You will need a sound level calibrator such as the Quest QC-10 complete the
following calibration procedures.
Coupler Microphone:
1. Use the arrow keys to select “Custom Coupler Mic Cal.”
2. Using the microphone adapter that is supplied standard with the FP35, fit
the coupler microphone into the calibrator. Turn the calibrator on.
3. Press [START/STOP] to begin the calibration.
4. Use the [∧, ∨] keys to adjust the coupler mic dB SPL until it matches that
of the calibrator. Pressing the keys briefly will result in 0.1 dB changes.
Holding the buttons down will result in 1 dB changes.
5. Once the coupler mic dB SPL matches the calibrator, press [EXIT] to return
to the Microphone Calibration Screen.
Probe Microphone:
1. Use arrow keys to select “Custom Probe Mic Cal.”
2. Couple the coupler mic and probe mic together using the calibration clip
(Figure C-1). Place the two at the center of the speaker cone in the sound
chamber.
