Chapter 2
7
Coupler Multicurve
In the Coupler Multicurve screen, you can view curves in dB SPL or dB Gain,
and run them with pure-tone, Composite, and Digital Speech signals (the latter
two are only available with the Composite Option.) Up to four curves can be
measured and displayed at the same time.
From the Opening screen of the FP35, enter the Coupler Multicurve screen by
pressing [F3].
2.1 Leveling
Leveling is the process by which the response of the sound chamber is mea-
sured and computer-corrected so that a “flat” sound field is achieved. In most
cases, leveling is performed using only the measurement microphone. This type
of leveling is accurate enough for most clinicial tests. See the Operator’s Manual
for information on leveling using the reference microphone.
1. Enter the Coupler Multicurve screen by pressing [F3] in the Opening
screen.
2. Open the sound chamber and place the coupler microphone at the center
of the speaker cone in the sound chamber.
If the microphone cables are not positioned properly, the chamber lid can
pinch, and eventually damage them.
Avoid damage by placing the cables
between the arrows
at the bottom of the speaker face. The foam on the
chamber lid is thicker and softer in this area, offering more protection.
3. Place the coupler that you will be using inside the chamber next to the
coupler microphone. This is necessary because of the small volume of the
FP35 internal sound chamber, and measurement results, particularly in
the high frequencies, could be affected by the space the coupler takes up
inside the chamber. See Figure 2.1.
4. Close the sound chamber lid.
5. Make sure the environment is as quiet as possible.
6. Press [F5], followed by [START/STOP], to level the sound chamber.
