Microphones/preamplifiers

Nor1239

Free-field microphone

The Nor1239 is a high-quality ½” free-field electret microphone that meets the Class 1 requirements for sound level meters specified in IEC 61672-1. It also complies with the working standard microphone specification IEC 61094-4, Type WS2F.

With a nominal sensitivity of 50 mV/Pa, Nor1239 can be used as a direct replacement for other prepolarised free-field microphones in this class. The use of high-grade materials combined with an artificial aging process results in an exceptionally stable microphone, engineered for demanding and long-term measurement applications.

Each Nor1239 is delivered with an individual calibration certificate, supporting traceable and standards-compliant acoustic measurements.

Get a quote

Specifications

Standards

Downloads

Specifications

Design: IEC 61094-4 Type WS2F
Frequency response: Free-field type
Nominal external diameter: 1/2-inch (13.2 mm)
Sensitivity level (nominal value): −26 dB (re. 1 V/Pa at 1 kHz) / 50 mV/Pa
Cartridge Capacitance (nominal value): 13 pF
Frequency range: 10 Hz to 20 kHz
Maximum input sound pressure level: 148 dBrms @ 3% distortion
Inherent noise (A-weighted equivalent sound pressure level): <16 dB
Temperature sensitivity (ref to 23°C @ 1 kHz):
<±0.35dB (−10°C to +50°C)
<±0.5dB (−20°C to +60°C)
Humidity (ref 23°C , 50% RH):
< ±0.14 dB max. (at 1 kHz, no condensation, 90% RH or less)
Atmospheric pressure sensitivity (ref 101.325 kPa @ 250 Hz):
<±0.4 dB from 85 kPa to 108 kPa
<±0.9 dB from 65 kPa to 85 kPa

Ambient temperature/humidity range for operation:
−20°C to +60°C, 90% RH (no condensation)
Ambient temperature range for storage: −20°C to +60°C
Dimensions (with protection grid): 13.2 mm diameter × 14.3 mm height
Preamplifier threads: 11.7 mm 60 UNS

Weight: 4.7 g
Warranty: 36 months