Maico MA 42, Руководство по эксплуатации

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Operating Instructions MA 42
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5.1.8 ABLB
The Alternate Binaural Loudness Balance test is a recruitment test. Alternating
tones between the two ears with headphones are used. The intensity of the
tone in the better hearing ear is varied until the loudness of the tone is judged
by the patient to be equivalent to a tone at a constant intensity in the normal
ear. This is called loudness balance.
To start the test select OT Test with the functional selector button (13), choose
ABLB, then the ABLB test screen will be displayed:
Figure 8 – ABLB screen
The test can be performed at all frequencies between 125 Hz and 8 kHz. Select
the test frequency by the frequency up and down key (4) and (5). Set the level
of the better hearing ear 5 dB above the threshold. Present the left or right
stimulus presenter bar (2). Adjust the level of the hearing-impaired ear with the
level control (1) until the loudness in both ears matches. Press the left or right
save button (3). Repeat the test for several levels.
To perform the test at another frequency, press the frequency up or down key
(4) or (5). A new ladder diagram appears. Use the functional selector button (9)
or (11) to jump to the previous or next diagram. Select 500 ms or 1000 ms as
modulation time by the functional selector button (13). To exit the ABLB test
screen press the EXIT button (6).
5.1.9 MLB
The Monaural Level Balance test is a test to detect perceived loudness
differences between two frequencies in the same ear. A tone with two
alternating frequencies is presented to the same ear. The level of the frequency
with normal hearing threshold is adjusted till it matches to the loudness of the
other frequency. The patient has to indicate if the loudness of both frequencies
is equal.