Measurement with XL2 Analyzer0 pages

.iNTi

OOOOOOOO000000 APPLICATION NOTE

AUDIO

Speech Intelligibility

Measurement with XL2 Analyzer

The XL2 Analyzer measures the speech intelligibility accord-

ing to the latest revision of standard IEC 60268-16:2011 (edi-

tion 4) and older editions. It includes ambient noise correction

and automated averaging of measurements.The XL2 displays

the measurement results as STI or as CIS results, accompa-

nied by the individual levels and modulation indices of the

seven octave bands.

STI and STIPA are the most established methods for measuring

speech intelligibility. STIPA is an optimized version of STI dedicat-

ed for portable measurement instruments. This application note

explains the principles behind these methods.

Index:

Introduction

Standards

XL2 Analyzer

STIPA Reporting Tool

STIPA Signal Source

STIPA Measurement Hints

Who can and should conduct STIPA measurements?

2

2

5

7

8

10

12

Appendix:

Subjective analysis methods 13

Technical Methods 13

STI - Speech Transmission Index 16

RASTI - Room Acoustics Speech Transmission Index 17

STIPA - Speech Transmission Index for Public Address 18

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