NTi Audio XL3 STIPA Speech Intelligibility Measurement

NTiAudio STIPA 01

The XL3 Acoustic Analyzer now supports speech intelligibility measurements according to IEC60268-16. Together with the TalkBox (acoustic) and MR-PRO (electrical) signal sources, the XL3 is the ideal tool for efficient and reliable STIPA measurement tasks. The measured values can be conveniently visualized in a report.

STIPA (Speech Transmission Index for Public Address Systems) measurements are carried out to evaluate the speech intelligibility of public address systems in different environments. Typically, STIPA measurements are performed in conference rooms and classrooms, on public transport announcement systems, at theatres, sports stadiums, hospitals and many more. If a public address system is designed for safety-related emergency announcements, the minimum requirement for STIPA values must be demonstrated by measurement and documentation. The STIPA test signal is fed, either acoustically or electrically, into the sound system. The STIPA values are then recorded with the XL3 at various points in the public area of interest. The measured values are displayed numerically and classified.

A significant factor for speech intelligibility is the presence of background noise. As it is often not convenient to play the STIPA test signal during typical operating times (e.g. a theatre full of people), the XL3 Acoustic Analyzer allows background noise levels to be recorded while the location is full, and STIPA measurements to be recorded separately, when the location is vacated. These measurements can then be combined later.

NTiAudio STIPA 02

The averaging of multiple measurements at one point is supported by a dedicated screen. Here the user retains the collected information about the individual measurements and the deviations between them. Invalid measurements can be disregarded immediately. With the STIPA Reporting Tool, which is available free of charge, the measurements at several positions can be conveniently summarized in a measurement report.

The STIPA function is available on the XL3 from firmware V1.36. You also need the 600 000 712 XL3 STIPA option. As an alternative to this permanent license, there is also a 365-day version 600 000 725 XL3 STIPA 365 Option. Firmware V1.36 is available to download free of charge for all XL3 devices.