Engineering Manual
137
UNIT
WALL
3.3ft
3.3ft
MICROPHONE
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0dB=0.0002 µbar)
BAND CENTER FREQUENCIES, Hz
PKA-A12HA7
PKA-A18HA7
High
NOTCH
Low
43
SPL(dB)
36
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB(0dB=0.0002 µbar)
BAND CENTER FREQUENCIES, Hz
PKA-A24KA7
PKA-A30KA7
High
Low
45
SPL(dB)
39
LINE
NOTCH
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0dB= 0.0002 µ
bar
)
BAND CENTER FREQUENCIES, Hz
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
High
NOTCH
Low
49
SPL(dB)
43
LINE
PKA-A36KA7