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Formant analysis bandwidth values

When I do a formant analysis, in the sdif-file, in the 1RES matrix there is bandwidth values. But what is the unit for them? Is it in Hz?
It might be because I do bad formant analysis on not suited material, but I can’t really make sense of the values I get.
I do my analysis using the om-superVP formant analysis, and then reading the results there by a sdif->text conversion.

Hi Anders,
Yes, bandwidtsh are in Hz.
You should read the results from your SDIFFile using GetSDIFData.
You can find out what are the right parameters by checking in the SDIF file contents, biut I think you will want:

  • SID (streamID) = 0
  • frametype = “1REB”
  • matrixtype = “1RES”
  • cnum = (0 1 2)

cnum = (0 1 2) means you will collect a list of (frequency / amplitude / bandwidth) for every formant and for every frame.
So you will end up with a list of lists (one for each frame/time) of lists (one for each formant) of the form (freq amp bw).

ps. alos note: for each frame (each element of this list) you ca use the function make-spec-env to reproduce the spectral envelope corresponding to the collected formant values.

Good to know. Thanks. I’ll try this out.
Thanks again for you help!