- Praat normalizes the maximum output of the AD converter to ±1. The amplitude scale of the waveform is adjusted to the largest and smallest value in the current signal (in this example 0.777 and -0.645).
- A practical advantage is that the waveform image is always magnified to the same size whatever the true amplitude. A disadvantage is that the scaling is different from recording to recording, which might be confusing to the viewer.The automatic amplitude scaling can be modified a little by turning the Sound autoscaling function on or off.
- With Sound autoscaling turned on, the amplitude scale is always adjusted to the maximum of the portion of the wave currently visible in the window (i.e. the scale changes continuously while scrolling).
- With Sound autoscaling turned off, the amplitude scale remains constantly set to the largest amplitude value of the entire signal while scrolling.