Directionality Measurements - Interacoustics Affinity 2.0 Additional Information

2.6.7

Directionality measurements

Unwanted noise will inevitably turn up in daily lif e situations. Fortunately, many digital hearing aids have
directional microphones that suppress noise coming f rom some directions while maintaining a good
sensitivity to sounds coming f rom another direction. This ef f ect can be measured in the real-ear.
Place the client in f ront the REM loudspeaker. First a response curve/f requency response is recorded f or
sounds coming f rom the f ront. Af ter this turn the client around f acing the opposite direction and a similar
curve will be recorded f or sounds coming f rom the back. Then the second curve is subtracted f rom the f irst
and results in the directionality curve.
If pref erred the directionality test can also be perf ormed using a f ree f ield speaker as the back speaker.
Test procedure:
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1) Open the REM440 module by selecting the REM tab.
2) Select a test in the List of Protocols. If a customized test setup is not created the REM440 will
automatically pick a standard test.
3) Explain the procedure to the client.
4) Perf orm otoscopic examination.
5) Mount the probe tube on the in-situ headset and place it on the client who should be seated in ½-1
meters distance f rom the speaker.
Ensure that the probe tubes are calibrated bef ore placing them in the ear canal (see section 0 about
tube calibration).
6) Caref ully insert the hearing aid without moving the probe tube. Ensure that the instruments are
switched on.
7) If f itting an open hearing aid solution, perf orm Calibrate for open fit (see section 0)
8) Click on the Directionality button if it is not already marked automatically.
A right click on Directionality button allows you to enter the Settings menu or Change colour of the
curve.
9) Check that the inf ormation about client, f itting prescription and hearing aid to the right are correct.
D-0004576-Q – 2022/05
Affinity/Equinox2.0 – Additional Information
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