Frye FONIX 7000, Руководство оператора

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Real-Ear Measurements
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7. Test as usual. With the reference microphone disabled, it is even more criti-
cal than usual that the patient not move after leveling and that the sound
field be undisturbed during testing.
6.8 Visible Speech
The Visible Speech screen, shown in Figure 6.8, is a special screen used for per-
forming real-ear measurements with live speech or other external source types.
The following features are displayed upon the Visible Speech screen before the
test has started.
Visible Speech was designed to demonstrate the real-time response of the hear-
ing aid to the speech signal, the average response of the aid over the time of
the test, and the minimum and maximum amplitudes of each frequency. These
measurements can be compared to the patient’s thresholds, uncomfortable lev-
els, real-ear target(s), and the long term average speech spectrum.
When first entering the Visible Speech screen (Figure 6.8), it has the following
characteristics:
1. Shaded areas below and above the patient’s patient’s threshold and uncom-
fortable values, respectively. The non-shaded area in the center of the graph
represents that patient’s dynamic range of hearing.
2. L, M. H dotted lines indicating the real-ear prescriptive targets at 50, 65, and
80 dB SPL. When NAL-NL1 is not the selected fitting rule, only the M target
(65 dB SPL) will be displayed.
3. l, m, h dotted lines indicating the unamplified the region of average
unamplified speech. These lines are called collectively the LTASS (long term
average speech spectrum). They can be used as a comparison against the
amplified speech response.