Delay time – NTi Audio XL2 Sound Level Meter User Manual
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Delay Time
Automated Difference Calculation
The delay time difference between speaker A and B is
•
automatically calculated and shown below the Act. Delay
result.
The delay time is measured.
Delay Test utilizes VoiceNote Microphone
The XL2 uses the internal VoiceNote micro-
phone to measure the acoustic delay. Do not
connect any measurement microphone to the
XL2 for the delay time measurement.
Measurement Position
Do not position the XL2 too close to reflecting
surfaces, such as walls or floors. The reflections
are likely to prevent accurate measurements.
Result Interpretation
The resulting time in milliseconds shows
•
the time difference of the sound signal from
speaker A and B arriving at the measurement
position. Speaker B has to be delayed by the
displayed difference result.
To optimize directionality, add a further 5 ms
•
to the calculated difference. The main signal
from speaker A then arrives at the measure-
ment position first. The acoustic signal from
sub speaker B arrives 5 ms later. This im-
proves the subjective directionality percep-
tion of the listeners.
Distance in meter/feet
The distance results in meter/feet are displayed
below for easy verification of the test results
accuracy. The readings are based on 330 m/s
sound speed at 0°C / 32°F.