Instruction Manual

Sound Level Meter Types 2245 – Instruction Manual Page 100 of 110
Periodic Testing of Acoustical Frequency Responses
This section gives the correction data that must be applied to sound levels displayed in
response to the sound pressure produced by Multifunction Acoustic Calibrator Type
4226, or in response to simulation of sound pressure by Electrostatic Actuator UA-0033,
in order to obtain the equivalent sound levels that would be displayed under reference
environmental conditions in response to plane progressive sinusoidal sound waves
incident from the reference direction or from random directions. See Table A. 24 and
Table A. 25 to view the data.
Table A. 24 Acoustical test with Multifunction Acoustic Calibrator Type 4226.
Correction data that must be applied to the readings of the sound level meter
in order to obtain equivalent sound levels that would be displayed in response
to plane progressive sinusoidal sound waves incident from the reference
direction or from random directions
Calibrator
Frequency
Correction Data
For Type 2245
Free-field 0°
Without
Windscreen
Expanded
Uncertainty
Correction Data
For Type 2245
Free-field 0°
With
Windscreen
UA-1765
Expanded
Uncertainty
Hz dB dB dB dB
32 0.0027 0.15 0.00 0.21
63 0.0514 0.13 0.05 0.20
125 0.061 0.12 0.06 0.20
250 0.075 0.12 0.07 0.20
500 0.185 0.14 0.15 0.20
1000 0.080 0.16 -0.08 0.22
2000 0.257 0.18 0.28 0.27
4000 0.829 0.24 0.67 0.31
8000 2.862 0.31 2.60 0.40
12500 5.153 0.48 4.85 0.54
16000 6.377 0.59 5.93 0.66