Användningsområden
- Ljudmätare
- General purpose
- Laboratorie- och fältmätningar
The key components that determines the accuracy of a sound level meter is the measurement microphone and its associated preamplifier. The effectiveness of these components in converting the acoustic signal into an electrical analogue set the maximum accuracy that can be achieved by the ensuing signal processing. Norsonic have a carefully balanced range of measurement microphones to suite a range of applications that complement modern instrumentation yet maintain traditional values.
We offer a broad range of 1/2″ and 1/4″ microphone preamplifiers.
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 – 20kHz) <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.
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.