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With Pitch settings... from the Pitch menu, you can determine how the pitch contour is displayed and how it is computed. These settings will be remembered across Praat sessions. All these settings have standard values ("factory settings"), which appear when you click Standards.
This is the most important setting for pitch analysis. The standard range is from 75 to 500 hertz, which means that the pitch analysis method will only find values between 75 and 500 Hz. The range that you set here will be shown to the right of the analysis window.
You should set the range to values appropriate for your speaker, but a problem is that speakers vary enormously in their pitch ranges. For many low-pitched (e.g. average male) voices, you may want to set the floor to 75 Hz, and the ceiling to 300 Hz; for many high-pitched (e.g. average female) voices, a range of 100-500 Hz may instead be appropriate. On the high side, some children can reach almost 2000 Hz when yelling; on the low side, creaky voice can go as low as 40 Hz; for the speakers you are investigating, you may therefore want to experiment with this setting.
Here is why you have to supply these settings. If the pitch floor is 75 Hz, the pitch analysis method requires a 40-millisecond analysis window, i.e., in order to measure the F0 at a time of, say, 0.850 seconds, Praat needs to consider a part of the sound that runs from 0.830 to 0.870 seconds. These 40 milliseconds correspond to 3 maximum pitch periods (3/75 = 0.040). If you set the pitch floor down to 25 Hz, the analysis window will grow to 120 milliseconds (which is again 3 maximum pitch periods), i.e., all times between 0.790 and 0.910 seconds will be considered. This makes it less easy to see fast F0 changes.
So setting the floor of the pitch range is a technical requirement for the pitch analysis. If you set it too low, you will miss very fast F0 changes, and if you set it too high, you will miss very low F0 values. For children's voices you can often use 200 Hz, although 75 Hz will still give you the same time resolution as you get for low-pitched voices.
This setting determines the units of the vertical pitch scale. Most people like to see the pitch range in hertz, but there are several other possibilities.
The Pitch menu also contains Advanced pitch settings....
© ppgb, March 31, 2019