Mitsubishi Electric Mr.Slim PLH42AK, Technical & Service Manual

Page: 21 / 73

OC193-19
8. NOISE CRITERION CURVES
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
A
VE B
AND SOUND PRESSURE LEVEL,
dB re 0.002 MICR
O B
A
R
BAND CENTER FREQUENCIES, Hz
PCH24EK
1
PCH30EK
1
Hi
Lo
NOTCH
50
43
SPL(dB) 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
A
VE B
AND SOUND PRESSURE LEVEL,
dB re 0.002 MICR
O B
A
R
BAND CENTER FREQUENCIES, Hz
PCH36EK
1
Hi
Lo
NOTCH
51
45
SPL(dB) 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
A
VE B
AND SOUND PRESSURE LEVEL,
dB re 0.002 MICR
O B
A
R
BAND CENTER FREQUENCIES, Hz
PCH42EK
1
Hi
Lo
NOTCH
51
45
SPL(dB) LINE
1m
1m
unit
about 1.4m
MICROPHONE
ceiling
Ambient temperature 27˚C
Test conditions are based on JIS Z8731