Chapter 5
45
2-CC Targets
In the 2-cc target screens, you can measure hearing aids using a coupler in a sound
chamber and compare them to a target. This type of testing is especially useful
when fitting a patient who is unable to sit still for a real-ear measurement, such as
an infant or a young child. There are two 2-cc target screens available: the Coupler
Target screen, which converts real-ear targets into coupler targets, and the Coupler
EarSim screen, which converts coupler measurements into simulated real-ear
measurements.
The Real-ear Option is required to access these screens.
In the Coupler Target screen, real-ear targets are converted into coupler targets so
that you can compare them to coupler measurements. Targets and measurements can
be displayed in either dB SPL or dB GAIN.
In the Coupler EarSim screen, the opposite approach is used, and actual real-ear
targets are displayed. When coupler measurements are taken, the response curves
are converted, using average or measured RECD transforms, into simulated real-
ear measurements, which can then be directly compared to the displayed real-ear
targets. Two displays are available: Insertion Gain and SPL. When the SPL display is
selected, the patient’s HTL and UCL values are also displayed on the screen. These
HTL and UCL values are identical to the ones that would be displayed in the real-ear
SPL screen.
The Coupler Multicurve (described in Chapter 2), Coupler Target, and Coupler
EarSim screens are all connected to each other by the [NEXT] and [BACK] keys,
similar to the way that the real-ear screens are connected to each other. Any
measurements taken in one screen are automatically converted to the other screens,
minimizing your measurement time.
Coupler
Multicurve
Coupler
Target
Coupler
EarSim