Interacoustics Affinity2.0 Quick Manuals page 44

When do I use Calibrate for Open Fit?
When performing REM the stimulus needs to be maintained at the point of the patients head to ensure an
accurate measurement is made.
This can be difficult when making REM measurements with Open Fit Hearing Aids because there is a lot of
sound which leaks out of the ear canal and on to the reference microphone. Therefore the method used to
perform REMs needs to be changed.
The two methods used are as follows:
1. Active Reference Method – this involves the external reference microphone on the REM headset
monitoring and altering the stimulus from the speaker during the measurement. This is the best method
to apply when measuring with occluding ear-pieces as there is minimal sound leakage onto the
reference microphone.
2
and Callisto™ is performing REM by default under this method.
The Affinity
2. Substitution or Stored Equalization Method – this involves a quick measurement prior to performing
your Real Ear Measures to store the distance of the headset from the speaker. This ensures that
constant signal intensity is maintained to achieve the measurement level at the patients head.
However, this requires your patient to be very still to ensure an accurate measurement.
This method of performing REM is activated following 'Calibrate for Open Fit'. This can be added as part
of your REM test battery.
Item No. 8105087 – 12/2013
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