Real-Ear Measurements On Open Fittings - Interacoustics Affinity 2.0 Additional Information

The REM440 allows f or showing real-ear measurements as both gain and response curves.
The gain curve is automatically generated f rom the response curve which allows you to choose which view
you pref er using the Gain and Response radio buttons below the graph:
2.5.4

Real-ear measurements on open fittings

The increasingly popular open f it hearing instruments have many advantages relating to comf ort, sound
quality, and cosmetics; however, they introduce implications when it comes to Real-ear verif ication.
In traditional Real-Ear Measurements a ref erence microphone supervises the amplitude of the signal
reaching the hearing instrument f rom the loudspeaker. If the input level is louder or sof ter than the selected
level, the ref erence microphone will decrease or increase the volume of the stimulus accordingly. This
ensures that the correct level enters the ear canal (Dillon 2001).
When perf orming Real-Ear Measurements on an open f itting, some f requencies may leak out of the ear
canal and into the ref erence microphone causing the input level to be reduced to compensate. This results
in an erroneous curve below the target!
This issue is solved by using Calibrate for open fit.
D-0004576-Q – 2022/05
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Affinity/Equinox2.0 – Additional Information