Frequency response (18 pF/small signal): 20 Hz ¬– 20 kHz: ±0,1 dB
Gain: Typ -0.1 dB (-0.2 with 20 pF)
Input impedance: 10 GΩ, 1.4 pF
Output impedance: 50 ohm typical
Noise (20 pF dummy mic.):
A-weighted < 2,2μV (typ 1,8μV)
Lin (20 Hz – 20 kHz) <6 μV (typ 3,8 μV)
Power supply:
Single: 28 V (1mA) to 120 V (2.8mA)
Dual: ±14 V(1 mA) to ± 60 V (2.8 mA)
Maximum signal output voltage (peak): ±10 to ±50 V (dep. on supply)
Temperature: -25°C to +70°C (operation)
Relative humidity: 0 – 90%
Dimensions:
Length: 83 mm
Diameter: Body: 12.7 mm/Ring: 14 mm
Weight: 36 g
EC classification: As for sound level meter Nor140.

Frequency response Nor1209 (Cs = 20 pF)
Noise considerations
text

The figure above shows the typical frequency spectrum of the inherent noise of the preamplifier Nor1209 in one-third octave bands for transducer impedance of 20 pF. The A- and Z-weighted levels are also shown. 0 dB corresponds to 1 μV or to the sound pressure level when the microphone has the sensitivity 50 mV/Pa. Note that a real microphone with resistive impedances will have a higher noise level than a dummy microphone with similar capacitance.