Audioscan Verifit - Manual (Page 79)

Verifit ® User's Guide Version 3.12  May 2015
16 RECD measurement
The RECD (real-ear to coupler difference) may be individually measured to improve the accuracy of hearing aid
fittings. The measurement procedure may be accessed by selecting RECD from the On-ear tests list or from the
Audiometry poster within Speechmap.
Calibration of RECD transducer
RECD values are stored and expressed as referenced to the HA-1 (ITE) coupler, however for ease of
measurement we calibrate the RECD transducer in the HA-2 (BTE) coupler.
1. Connect the RECD transducer to the RECD jack on the front of the test chamber. Prepare the system for test
box tests. See Microphone connection, Calibrating test box reference microphone.
Prepare the system for test box tests. See Microphone connection, Calibrating test box reference microphone.
2. Press <Tests> then highlight and <PICK> [On-ear measures], then highlight and <PICK> [RECD].
3. When prompted, select the coupling (foam tip or mold) that will be used for the on-ear RECD measurement.
4. If a valid RECD transducer calibration exists, go to RECD on-ear response.
5. If no calibration exists or the measurement interval has been exceeded, connect the BTE coupler to the
coupler microphone and connect the RECD transducer to the BTE coupler.
6. Highlight and <PICK> [Calibrate RECD transducer] and follow the setup instructions.
7. Press <Continue> to generate the coupler response curve (green). When this curve is stable, press
<Continue> to save it.
8. Highlight and <PICK> [Daily] or [Weekly] to toggle the measurement interval for the coupler response.
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