Referencing - Interacoustics Affinity 2.0 Additional Information

2.5.7

Referencing

Ref erencing is the term used to describe the communication between the REM speaker and the Insitu REM
headset ref erence microphone. This communication ensures that the stimulus level specif ied in the REM
sof tware is the correct stimulus level achieved at the patients' ear.
As an example, if the level specif ied in the sof tware is set to 65dB and the REM speaker is playing at 55dB
then the Insitu ref erence microphone will detect this and communicate to the speaker that it needs to
increase the stimulus level by +10dB to achieve the specif ied stimulus level.
There are two dif f erent ref erencing procedures which can be perf ormed using your Af f inity Compact/Affinity
2.0/Equinox 2.0/Callisto.
They are according to the f ollowing:
Modif ied Pressure with Concurrent Equalisation (MPCE)
•
This method actively monitors and controls the level of the REM stimulus as it is running. Theref ore,
if the stimulus level drops during the measurement the speaker will increase the intensity, so the
correct level is applied.
This method is applied to the f ollowing signals:
Pure Tone
-
- Warble
- Pink Noise
- White Noise
NB Noise
-
Modif ied Pressure with Stored Equalisation (MPSE)
•
This method perf orms the ref erencing process at the beginning of the measurement only and the
level is set bef ore the REM stimulus is played. This is done because the signals used f or this method
are complex and do not maintain the same f requency content at dif f erent time points.
Note: f or signals which are being ref erenced by the MPSE method, the stimulus level will not
increase/decrease should the level at the Insitu ref erence microphone not match that which is set in
the sof tware once the REM stimulus begins to play. It is because of this that you must maintain the
patients' position during the measurement. The ref erencing procedure is still played bef ore every
stimulus though.
D-0004576-Q – 2022/05
Affinity/Equinox2.0 – Additional Information
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