Accuracy
Frequency weighting ( 31.5 Hz to 16 KHz )
(23± 5 )
℃
meet IEC 61672 Class 1, calibrating input
signal on 94 dB, then the accuracy of A/C
weighting is specified as following :
31.5 Hz - ± 2.0 dB, 63 Hz - ± 1.5 dB,
125 Hz - ± 1.5 dB 250 Hz - ± 1.4 dB,
500 Hz - ± 1.4 dB, 1 KHz - ± 1.1 dB
2 KHz - ± 1.6 dB, 4 KHz - ± 1.6 dB,
8 KHz - + 2.1 dB to -3.1 dB,
12.5 KHz - + 3.0 dB to -6.0 dB,
16 KHz - + 3.5 dB to -17.0 dB.
Characteristics of A & C.
A weighting :
The characteristic is simulated as "Human
Frequency
Ear Listing" response. Typical, if making
Weighting
the environmental sound level measurement,
Network
always select to A weighting.
C weighting
The characteristic is near the "FLAT"
response. Typical, it is suitable for
checking the noise of machinery (Q.C.
check) & knowing the sound pressure level of
the tested equipment.
Frequency
31.5 Hz to 16.0 KHz.
Calibrator
B & K (Bruel & Kjaer) :
Multi-fuction acoustic calibrator,
model : 4226.
Microphone
Electric condenser microphone.
Size of
0.5 inch standard size.
Microphone
Range
30 to 70 dB, 60 to 100 dB, 90 to 130 dB,
Selector
40 dB on each step, with over & under
range indicating.
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