Formant Settings

Settings for Formant analysis.

Adapted from http://www.fon.hum.uva.nl/praat/manual/Sound__To_Formant__burg____.html

The Formant settings window can be opened by choosing Formant settings... from the Praat menu in the Speech Analysis view of the Session Editor window.

Time step (s): the time between the centres of consecutive analysis frames. If the sound is 2 seconds long, and the time step is 0.01 seconds, there will be approximately 200 analysis frames.
Maximum number of formants: for most analyses of human speech, you will want to extract 5 formants per frame. This, in combination with the Maximum formant setting, is the only way in which this procedure will give you results compatible with how people tend to interpret formants for vowels, i.e. in terms of vowel height (F1) and vowel place (F2). Otherwise, the Maximum number of formants can be any multiple of 0.5, you can choose 4, 4.5, 5, 5.5, 6, and so on.
Maximum formant (Hz): the ceiling of the formant search range, in hertz. It is crucial that you set this to a value suitable for your speaker. The standard value of 5500 Hz is suitable for an average adult female. For a male, use 5000 Hz; if you use 5500 Hz for an adult male, you may end up with too few formants in the low frequency region, e.g. analysing an [u] as having a single formant near 500 Hz whereas you want two formants at 300 and 600 Hz. For a young child, use a value much higher than 5500 Hz, for instance 8000 Hz (experiment with it on steady vowels).
Window length (s): the effective duration of the analysis window, in seconds. The actual length is twice this value, because Praat uses a Gaussian-like analysis window with sidelobes below -120 dB. For instance, if the Window length is 0.025 seconds, the actual Gaussian window duration is 0.050 seconds. This window has values below 4% outside the central 0.025 seconds, and its frequency resolution (-3 dB point) is 1.298 / (0.025 s) = 51.9 Hz, as computed with the formula given at Sound: To Spectrogram.... This is comparable to the bandwidth of a Hamming window of 0.025 seconds, which is 1.303 / (0.025 s) = 52.1 Hz, but that window (which is the window most often used in other analysis programs) has three spectral lobes of about -42 dB on each side.
Pre-emphasis from (Hz): the +3 dB point for an inverted low-pass filter with a slope of +6 dB/octave. If this value is 50 Hz, then frequencies below 50 Hz are not enhanced, frequencies around 100 Hz are amplified by 6 dB, frequencies around 200 Hz are amplified by 12 dB, and so forth. The point of this is that vowel spectra tend to fall by 6 dB per octave; the pre-emphasis creates a flatter spectrum, which is better for formant analysis because we want our formants to match the local peaks, not the global spectral slope.
Dot size: Size of formant dots in the display. Use increments of .5 (e.g., 1.5, 2, 2.5, etc.).

Settings for formant listings:

Include num formants: Include number of formants column
Include intensity: Include intensity column
Include bandwidths: Include a bandwidth column for each formant