FONIX® 8000 - Frye Electronics

160 FONIX 8000 Hearing Aid Analyzer
5. If you have selected NAL-NL1, or MOD NAL, the following menu settings
are also available:
• Compression: The compression kneepoint of the hearing aid. If the hearing
aid has multiple compression kneepoints, use the first one.
• No. of Channels: The number of channels of the hearing aid.
• Aid Limit: Type of output limit employed by the aid. Choose from
Multichannel or Wideband.
• Fit Type: Type of hearing aid fitting used by the patient. Choose Unilateral
or Bilateral.
• Sound Field: Position of the sound field speaker during real-ear measurements.
If the patient’s threshold values were measured with a sound field
speaker, the same angle used for the audiometric measurements should be
used for the real-ear measurements.
• Ref. Position: Type of leveling used for the real-ear measurement. Head
surface includes the patient inside the sound field (recommended for best
accuracy). Undisturbed Field indicates leveling was done by holding the
reference microphone in front of the sound field speaker.
6. Press [EXIT] to close the menu. If you are in a real-ear measurement
screen, you should see the new selected fitting rule noted under the Curve
Characteristics box.
8.3.4 Entering Bone Data
The NAL-NL1 and MOD NAL targets use bone data in their calculations. If the
patient’s bone thresholds are not entered, they will assume average values. No
other fitting rules use the bone data. To enter this data:
1. Press [MENU] in the Audiogram Entry screen to open the local menu.
2. Set the FITTING RULE to NAL-NL1 using the arrow keys.
3. Press [EXIT] to exit the local menu.
4. Press [F2] repeatedly until BONE is selected.
5. Use the arrow keys to enter the bone values into the appropriate column of
data.
8.3.5 Performing an RECD measurement
The real-ear to coupler difference (RECD) is the acoustical difference between a
2-cc coupler and the real-ear occluded response of an individual. It involves a
coupler measurement and a real-ear measurement. Both measurements are usually
performed with an insert earphone as the transducer.
It’s also possible to use a linear hearing aid, instead of an insert earphone, to
perform the RECD test. In this case, you would use the same hearing aid, set
with identical volume control and/or other settings, for both the coupler and
real-ear portions of the test. The DSL Method does NOT recommend using a
hearing aid as the RECD transducer.