Frye FONIX 7000 - Manual (Page 141)

Real-Ear Measurements
133
3. Press [F5] to select the Composite signal as the source type.
4. Press [START] to start a measurement.
5. Insert the probe tube carefully, looking at the composite measurement. At
some point, there will be a large dip below the 0 dB level at 6 kHz caused
by the standing wave inside the ear. Keep inserting the probe tube until that
dip goes away and the unaided response is above 0 dB gain between 6 kHz
and 8 kHz. See Figure 6.2.3B.
6. Press [EXIT] to return to the Real-Ear Navigation screen.
Hints: To help keep the probe tube in place, position the tube so that it runs
through the tragal notch, resting against the lower edge of the tragus. If neces-
sary, reposition the body of the probe microphone lower on the Velcro button of
the ear hanger. If desired, use surgical tape to hold the tube in position.
Figure 6.2.3B—Unaided response with correct insertion of the probe tube
6.2.4 Leveling the Sound Field Speaker
The first step in making real-ear measurements is to level the sound field speak-
er. The sound field includes the room and everything in it: the operator, the cli-
ent, and any ambient noise that may penetrate the room. Leveling is important
so that the input to the hearing aid is properly controlled across the frequency
spectrum. See Figure 6.2.4. You must re-level the sound field for every client
and every ear.