11
90
80
70
60
50
40
30
20
10
63
125
250
500
1000
2000
4000
8000
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCT
AVE BAND SOUND PRESSURE LEVEL, dB ( 0dB = 0.0002 µbar )
BAND CENTER FREQUENCIES, Hz
PCA-RP71HAQ
PCA-RP71HAQ-ER
NOTCH
High
Low
SPL(dB)
38
34
LINE
90
80
70
60
50
40
30
20
10
63
125
250
500
1000
2000
4000
8000
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCT
AVE BAND SOUND PRESSURE LEVEL, dB ( 0dB = 0.0002 µbar )
BAND CENTER FREQUENCIES, Hz
PCA-RP125HAQ
NOTCH
High
Low
SPL(dB)
50
44
LINE
1m
1m
unit
about 1.4m
MICROPHONE
ceiling
NOISE CRITERION CURVES
5
OCH492A
