Dismantle the probe

Before any calibration can be done, the probe must be dismantled. For the Nor1290 probe, please follow the link below for instructions:

Dismantle Nor1290

Setting up parameters

First, make sure the intensity probe is selected as the input channel. Press CAL to enter the calibration menu. Set up the microphone spacer (12 mm recommended). More information:

Selecting spacer

Input values of the measurement environment:
- Ambient temperature
- Ambient pressure

Pressure calibration

Tap Pressure Calibration to enter the pressure calibration mode.

Insert the microphone in the "A" position of the probe into a regular class 1 sound pressure calibrator. Tap Sound Channel 1 and perform a regular microphone calibration.

Repeat the procedure for the second microphone.

Phase calibration

Back in the calibration menu, tap Phase Correction to enable the phase correction mode. Insert both microphones into the Nor1294 Phase Calibration Coupler. Be careful to make sure the ventilation is open when inserting the microphones, and ensure both microphones are completely inserted before closing the ventilation.

Connect the Nor1294 to the headset connector on the Nor150 (picture below).

Handling the Nor1294

Press START to begin calibration. For the best results, the probe and calibrator should not be placed on a vibrating surface.

When calibration is done, the Pressure-residual intensity index is displayed, along with the IEC 61043 minimum values. Both the pressure-residual intensity index and the minimum values depends on the current spacer setting, however, the difference between minimum values and the pressure-residual intensity index will remain constant when changing spacer.

More information

Handling the Nor1290

Handling the Nor1294

Intensity probe theory

Phase calibration theory

Getting started with Sound Intensity

Sound Intensity help index