User manual

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STIPA
Display of STIPA Numeric Result Page
The symbol indicates that the averaged STI value is dis-
played.
Ambient Noise Correction
Measuring the speech intelligibility index under realistic envi-
ronmental conditions is often not feasible; e.g., playing the test
signal in a railway station at emergency levels during peak hours
will irritate passengers. Additionally, at rush-hour the charac-
teristics of ambient noise might be highly impulsive, while a
pre-requisite for accurate speech intelligibility measurements
is a negligible impulsivity in the ambient noise. Under such cir-
cumstances the speech intelligibility measurement should be
shifted to a more suitable time of the day; e.g. night time.
Measurement Sequence
First measure the ambient noise•
Secondly measure the speech intelligibility•
This sequence simplifies the measurement
as follows: The XL2 immediately displays the
speech intelligibility result with ambient noise
correction. This result provides a guideline if
repeated measurements at the same location
with averaging is required. For details see the
chapter STIPA Measurement Hints.