64 FONIX FP35 Hearing Aid Analyzer
Press down on the Fun-Tak with a
pencil or your finger to create an
acoustic seal between the aid and
coupler.
You may want to double-check the
aid placement through the open
end of the coupler at this point.
Slowly insert the microphone into
the coupler. You may feel an initial
resistance when the mic reaches
the O-ring. Continue to push the
microphone until it stops.
Place the completed assembly over
the center of the speaker in the test
chamber. With ITEs, the position
of the aid can affect the frequency
response. Point the faceplate to the
right or left. Place the mic cable
between the arrows (secure it with
a bit of Fun-Tak if necessary). The
Velcro on the coupler will help
hold the assembly in place. Be con-
sistent with your setup for repeat-
able results.
Set the hearing aid’s gain control to
the desired position, and adjust the
source level to the desired ampli-
tude.
3.3.3 Setting up a Body Aid
Place the hearing aid into the sound chamber so that the microphone of the aid
is centered over the speaker. Adjust the tone and gain controls to the desired
positions. Insert the FP35 microphone into the HA-2 coupler and snap the
receiver onto the end of the coupler (you will not need the ear level adapter for
this setup). Place the coupler outside the sound chamber and close the lid if
possible.
Adjust the source level to the desired test drive amplitude.
3.4 Frequency Responses
In the Coupler Multicurve Mode of the FP35, you can perform the following
measurements: response curves, single-frequency measurements, harmonic dis-
tortion, and intermodulation distortion.
