Coupler Measurements 83
Figure 3.8.5—Curve 1 is the measurement microphone. Curve 2 is the reference microphone
3.8.6 Changing the Signal Filters
Filters are the type of speech weighting applied to the test signals as they are
presented to the hearing aid. By default, the FP35 analyzer automatically
chooses the appropriate speech weighting to use with a particular type of signal.
For instance, when you use a pure-tone signal, a flat weighting is used. That is,
every frequency of the pure-tone sweep has the same amplitude. When you use
the composite signal, the Frye ANSI speech weighting is used. That is, the low
frequencies have higher amplitudes than the higher frequencies.
The FP35 analyzer allows you to specifically choose the type of speech weight-
ing you want to use. You do this by altering the FILTER selection in the
Advanced Menu of the Coupler Multicurve and Target Coupler screens and the
Real-Ear Measurement Screens. See Section 2.5.2.1 for a more information.
To change the filter in the Coupler Multicurve or Target Coupler screen:
1. Press [MENU] from the measurement screen to enter the local menu.
2. Press [NEXT] to enter the Advanced menu.
3. Use [∨, ∧] to select FILTER.
4. Use [<, >] to select the desired filter type. See Section 2.5.2.1 for an expla-
nation of the available selections.
5. Press [EXIT] to return to the measurement screen. The filter type you have
chosen will now be in effect.
