Svantek SV 977D - Page 244

244
SV 977D User Manual - Appendixes
Microphone
MK 255 prepolarised free-field ½” condenser microphone
Nominal sensitivity 50 mV/Pa (corresponding to -26 dB re 1 V/Pa)
Capacitance 17 pF
Reference point geometric centre of the microphone diaphragm.
Note: Maximum sound pressure level that can be applied to a microphone without destroying it:
146 dB.
Typical MK 255 Free Field frequency response (source: Microtech Gefell Gmbh)
Table C.1.4. MK 255 free field corrections using the electrostatic actuator for 0 deg incidence angle
[dB]
Frequency [Hz]
20
25
31.5
40
50
63
80
100
125
160
200
250
315
400
500
630
800
Correction
factors
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
-0.05
-0.07
-0.07
-0.06
-0.04
Uncertainty
(IEC 62585)
--
--
--
--
--
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
[dB]
Frequency [Hz]
1000
1250
1600
2000
2500
3150
4000
5000
6300
8000
10000
12500
16000
20000
Correction
factors
-0.04
-0.03
0.02
0.13
0.30
0.55
1.00
1.55
2.21
3.35
4.83
6.94
9.16
11.59
Uncertainty
(IEC 62585)
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.35
0.35
0.35
0.35
0.50
0.50
0.50
Preamplifier
SV 12L nominal preamplifier attenuation: 0.7 dB;
IEPE Type – power supply 1.5 mA@30 V