NTi Audio Acoustilyzer AL1 User Manual

Page 55

b. How to measure

• Select the STI-PA function.
• Monitor the actual sound pressure level

of your environment on the Acoustilyzer

display.

Preconditions:
• To avoid measurement failures the

STI-PA test signal level should be

at least 60 dBSPL.

• The STI-PA measurement should be

carried out in simulated emergency

conditions (same sound pressure level

and all components activated).

• No impulsive noise events should occur

during the 15 seconds measurement

time.

NOTE: Even intermittent noise may affect

the STI-PA test result.

Signal Source:

The

NTi Audio TalkBox can simulate a

human talker at normal and emergency

speaking levels, enabling the measurement

of the complete system including the

acoustic signal to the microphone

(directivity, room characteristics, etc). Place

the NTi Audio TalkBox at the typical human

speaker position.

The

Minirator MR-PRO or a CD Player (with

the NTi Audio CD “STI-PA V1.1” or higher)

can be used for electrical signal injection for

system tests without the microphone.