The Norsonic Nor1256 Electronic Multi-Level Acoustic Calibrator is a small, battery-operated Class 1 sound calibrator conforming to IEC 60942 and ANSI S1.40 standards. The Nor1256 generates a sinusoidal signal of 250 Hz or 1 kHz at 94 dB or 114dB. The combination of two different levels and two different frequencies allow both level and frequency linearity to be verified. In addition, the sound calibrator can measure environmental conditions including air pressure, temperature, and relative humidity.

The calibration level, frequency and environmental parameters are displayed on a high contrast OLED display. A push on the dB button toggles between 94 and 114dB. Likewise a push on the Hz button toggles between 1000 and 250Hz. The °C/°F button displays the ambient pressure, temperature and humidity.

Sound is produced by a small loudspeaker built into the acoustic coupler, while an internal reference microphone monitors the output. A feedback circuit automatically adjusts the level, ensuring the calibration signal remains essentially unaffected by environmental factors such as temperature, air pressure, and humidity within the specified operating range.

The Nor1256 is designed for use with 1-inch and smaller microphones, as well as sound level meters equipped with them. One-inch microphones fit directly into the coupler, while a Nor4583 adapter for ½-inch microphones is included, and a Nor4589 adapter for ¼-inch microphones is available as an optional accessory.

The Nor1256 operates on two LR03 alkaline (AAA) batteries. If the battery voltage drops too low for reliable performance, the unit will automatically shut down or fail to power on.

Each unit comes with an individual accredited calibration certificate and a three-year warranty.