The frequency response of a transducer/sensor can be modified by adding correction factors for the individual third octave frequencies.
Set level

Tap on a frequency and adjust the level with the wheel.

At the bottom of the screen there is a small graph indicating the selected corrections. The information is stored both together with the transducer setup and with all measured results and can therefore be turned on and off after the measurement is finished. This is typically done in postprocessing software.