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Microphone [GA216I, GA216B, GA216L, GA257B, GA257L]
MK79 ACO ½“ Electret Condenser Microphone Cartridge Type 7052.
Microphone reference point is the centre of the diaphragm.
Type MK79 (ACO 7052)
Specification
Diameter (inch)
0.5
Response Type
Free-Field
Polarization (V)
0.0
Frequency Range (Hz)
20 - 8000
Sensitivity (mV/Pa)
25.0
Sensitivity (dB re 1V/Pa)
-32.0 ±1.5dB
Capacitance (pF)
18.0
Max. Sound Pressure Level (dB)
146.0
Temperature Coefficient (dB/°C)
-0.01
The pressure to free-field correction value to be applied when used with a Castle
calibrator GA601/GA607 or B&K4231 is as follows:
-0.2dB
The capsule can be removed by unscrewing anti-clockwise although great care
must be taken when doing this to avoid damage to either the capsule or the
instrument. Re-fitting is a reverse of the above.
Type MK79 (ACO 7052) Typical Microphone Response
31.5Hz
0.2
1kHz
0.0
63Hz
0.1
2kHz
0.0
125Hz
0.0
4kHz
0.0
250Hz
0.0
8kHz
0.5
500Hz
0.0
Typical Actuator to free field correction factors(dB) of an MK79
(ACO 7052) microphone (Based on 500Hz = 0)
20Hz
0.0
500Hz
0.0
25Hz
0.0
630Hz
0.0
31.5Hz
0.0
800Hz
0.0
40Hz
0.0
1kHz
0.1
50Hz
0.0
1.25kHz
0.2
63Hz
0.0
1.6kHz
0.3
80Hz
0.0
2kHz
0.4
100Hz
0.0
2.5kHz
0.5
125Hz
0.0
3.15kHz
0.8
160Hz
0.0
4kHz
1.2
200Hz
0.0
5kHz
1.6
250Hz
0.0
6.3kHz
2.3
315Hz
0.0
8kHz
3.6
400Hz
0.0
