NTi Audio XL2 Sound Level Meter - Manual (Page 130)

130
STIPA
Hints: CD-Player
Only high-quality CD-Players should be used to reproduce •
the STIPA test signal as only limited time-shifts (+/- 20 ppm)
ensure reliable STIPA test results. Pitch control and shock
protection should be disabled. We recommend that only
professional CD-Players be used. Verify the time shift of the
CD-Player with a 1 kHz test signal:
Insert the NTi Audio Test CD into the CD-Player and start •
track 1, which is the 1 kHz test signal.
Connect the XL2 directly to the audio output and mea-
•
sure the signal frequency in RMS/THD+N mode. The dis-
played frequency should be in the range from 0.99998
kHz to 1.00002 kHz
STIPA test signals from other test system manufacturers •
may sound similar but are not compatible. Only the NTi Au-
dio STIPA test signal CD V1.1 or higher should be used in
combination with the XL2.
Hints: Measurement
Select typical locations based upon such regulations, or typi- •
cally position the microphone at 1 - 1.2 meters above ground
in sitting areas or 1.5 - 1.8 meters in standing areas (typical
positions are not directly in front of the speakers).
The person taking the measurements should be out of the •
acoustic field, so as not to affect the measurement results.
For this purpose the measurement microphone can be
mounted on a microphone stand and connected with the
ASD-Cable to the XL2.
Low STIPA readings can be caused by •
Excessive sound reverberation, echoes or reflections •
Poor speaker directivity or speaker coverage •
Speaker level setting incorrect; e.g. low signal-to-noise •
ratio.