The Nor150 is equipped with octave and 1/3rd octave filters in the standard version. The covered frequency range is 0.1 Hz to 20 kHz in 1/3rd octaves and 0.125 Hz to 16 kHz in octaves.
Filter bandwidth
The operator can select the upper and lower frequency limits for the measurement.
Filter frequency selection
As an extension 1/12th octave and 1/24th octave filters can be selected. The upper frequencies of these filters can only be measured in real time in one channel operation.

Please note that the weighting networks always are measured with the full frequency range independant of the filter settings.