No influence

This option does not take the background noise into account, and can be used to assess the detrimental effects of reverberation on speech intelligibility separated from the effects of noise. It only requires a reasonably high quality impulse response measurement. No calibration of either source or microphone is needed.

The calculations are based solely on modulation reduction caused by the impulse response, thereby assuming that the normal speech-to-noise ratio in the space is greater than 15 dB in the octave bands of interest. This happens in rooms where the effects of reverberation and reflections usually dominate.

For maximum accuracy the impulse response should not be noise contaminated, and the calculation should be performed with  turned on. This setting is found in Calculate->Calculation Options… by clicking the  button.

Note: If  is turned off, and no other truncation and no averaging is performed, the calculation will be the similar to using the option Correction using background noise in measurement.