Stipa – NTi Audio XL2 Sound Level Meter User Manual
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STIPA
1
Run Indication
This icon displays the run status of the STIPA measure-
ment.
2
Measurement Result
Single value speech transmission index result.
•
Repeatability of measurement result:
•
Since a dedicated noise test signal is used, the STIPA
result may deviate by maximum 0.03 STI (=Max-Min) at
the same measurement position.
3
Sound Level LAeq
Shows the time-averaged sound level of the 15 seconds
STIPA measurement cycle time.
4
Sound Level LAS
Actual sound pressure level.
5
Analog STIPA Bargraph
Bargraph display and interpretation of the speech intelligi-
bility measurement result
Exlnt
0.75 - 1.00 STI
•
Good
0.60 - 0.75 STI
•
Fair
0.45 - 0.60 STI
•
Poor
0.30 - 0.45 STI
•
Bad
0.00 - 0.30 STI
•
6
Qualification Scale
The STI value is shown as a letter of the qualification scale
below, which informs about the typical STI requirements
for dedicated applications.
Band
STI Range
Examples of typical uses
A+
> 0.76
recording studios
A
0.72 - 0.76
theatres, speech auditoria,
parliaments, courts
B
0.68 - 0.72
theatres, speech auditoria,
parliaments, courts
C
0.64 - 0.68
teleconference, theatres
D
0.60 - 0.64
class rooms, concert halls
E
0.56 - 0.60
concert halls, modern churches
F
0.52 - 0.56
PA in shopping malls,
public offices, cathedrals
G
0.48 - 0.52
PA in shopping malls,
public offices
H
0.44 - 0.48
PA in difficult acoustic
environments
I
0.40 - 0.44
PA in very difficult spaces
J
0.36 - 0.40
not suitable for PA systems
U
< 0.36
not suitable for PA systems