NTi Audio XL2 Sound Level Meter - Manual (Page 85)

85
Reverberation Time RT60
Error Indications
Various error indications are displayed for unsuccessful RT60
measurements. Corrupt cycles can be deleted individually.
These results are then excluded from the average calcula-
tions.
LOW LEVL •
This is the abbreviation of “low test signal level” during the
measurement. Increase the test signal level until the black
level markers exceed the grey level markers in every fre-
quency band. Also, ensure that the level falls below the grey
level markers, otherwise use a RT60 test signal with longer
on/off times.
CORR<70% •
The correlation factor is lower than 70% indicating an unreli-
able measurement result.
T>18S •
The measured reverberation time exceeds the time limit of
18 seconds. This is commonly caused by either an incorrect
analyzer range setting or environmental noise. In the first
case, choose another range setting. In the second case, en-
sure that the environmental noise remains constant during
the measurement, and/or SET the level markers again while
the environmental noise is high.