Instruction Manual

Sound Level Meter Types 2245 – Instruction Manual Page 80 of 110
Free-field Frequency Responses for Diffuse-field Calibrated
Instruments
Free-field frequency response in the reference direction for diffuse-field calibrated
instruments according to IEC 60651 and IEC 60804. Measured with plane progressive
sinusoidal sound waves incident from the reference direction and the sound level
meter’s Sound field set to Diffuse-field , see section 4.6.
Table A. 6 Free-field 0° frequency response with the Sound field set to Diffuse-
field for the configurations for which there are specified normal Free-field
responses
Nominal
Frequency
Exact
Frequency
(6 digits)
Configuration
as in
Table A.2
Configuration
as in
Table A.3
Hz Hz dB dB
63 63.0957 0.07 0.07
80 79.4328 0.07 0.07
100 100.000 0.06 0.06
125 125.893 0.06 0.06
160 158.489 0.06 0.06
200 199.526 0.07 0.06
250 251.189 0.08 0.07
315 316.228 0.12 0.10
400 398.107 0.16 0.13
500 501.187 0.19 0.14
630 630.957 0.11 0.04
800 794.328 0.00 -0.11
1000 1000.00 0.09 -0.07
1060 1059.25 0.10 -0.08
1120 1122.02 0.09 -0.10
1180 1188.50 0.10 -0.11
1250 1258.93 0.11 -0.13
1320 1333.52 0.13 -0.12
1400 1412.54 0.16 -0.12
1500 1496.24 0.17 -0.13
1600 1584.89 0.16 -0.16
1700 1678.80 0.19 -0.15
1800 1778.28 0.22 -0.15
1900 1883.65 0.22 -0.17
2000 1995.26 0.29 -0.11
2120 2113.49 0.06 -0.35
2240 2238.72 0.30 -0.12
2360 2371.37 0.56 0.12
2500 2511.89 0.50 0.06
2650 2660.73 0.34 -0.09
2800 2818.38 0.47 0.05
3000 2985.38 0.74 0.35
3150 3162.28 0.69 0.33
3350 3349.65 0.58 0.26
3550 3548.13 0.89 0.61