Correction, noise updated automatically

This option is similar to the above, except that the Noise octave band corrections shown in the figure above are computed and updated automatically from the tail of the measured impulse response. In order to do this, the input chain (including the microphone) must be calibrated. The background noise is computed from the last 10000 samples of the tail. Make sure that the measured impulse response has decayed sufficiently.
Please note that this option should not be used on measurements performed using averaging since the averaging will reduce the effect of the background noise. Therefore use 1 averaging, and an impulse response length larger than 1 second (in a reverberant room, larger than 2 seconds).

The MTF itself can be displayed by selecting it in Room Acoustics->Parameter Settings....