otometrics madsen itera ii, Справочное руководство

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7.2.1 One-channel or two-channel Speech testing
To select one or two input channels, see Selecting input
►
69 .
If you wish to operate MADSEN Itera II as a one-channel or a two-channel Speech audiometer, select either the same input
to both ears (one-channel) or select two different inputs (two-channel).
One-channel binaural test-
ing (default) CD_1 is the default input channel for both ears. If you wish to use CD_2 for one-channel
testing, you must change both input channels.
• The stimulus level is interlocked and cannot be adjusted separately.
• Masking is available on the audiometer.
Two-channel binaural test-
ing Select two different input channels, one for each ear.
• The stimulus levels can be adjusted independently.
• Masking is available on the audiometer.
7.2.2 Adjusting input sensitivity
You can adjust the strength of the input signal:
1. Press and hold the selected input button and use the right LEVEL selector to adjust the strength of the input signal in
the channel which is flashing on the display.
2. Press
L <--> R
to toggle to the opposite input channel to be able to adjust its sensitivity. To calibrate the speech sig-
nal, the VU meters must move into line with "0 dB" on the VU meter scale.
Caution
•
You should only use speech materials with a stated relationship between the level of the speech signal and
the calibration signal.
Speech materials delivered on CD or other media are normally accompanied by a description of this relationship. You
should follow the instructions supplied with the speech materials, using the VU-meter in OTOsuite for adjustment of
input gain
7.3 Special Speech routing
7.3.1 Mixing input signals for two-channel monaural Speech
Note
• If masking noise is switched on, the input signals cannot be mixed (see Binaural Speech with masking
►
73 ).
• If you press and hold
CD
or
MIC
and then press
L <--> R
, the selected
test input source is sent to the left ear, indicated by an arrow from right
to left.
• Press once more to send the input to the right ear.
72 Otometrics - MADSEN Itera II
7 Speech testing