Dear Reg
You ask for a reference in relation to my assertion that >there is an absence of even harmonics in a square wave as >derived during one mode of the open and closed functions of >the cords.
No, my question was not in regard to the analysis of a square wave (but thank you for the trouble you went to in reproducing the formulae). The question related to your statement:
>My answer...not falsetto. Falsetto implies an almost total >absence of ODD harmonics of the fundamental frequency.
I am interested that you see a square-waved pattern in the vocal source. The flow glottograms I have seen of falsetto have never suggested a square wave to me but more a waveform approaching sinusoidal. It is unclear to me what would cause the sharp changes in the waveform essential to the square-waved pattern: the rapid rise in flow, sharp change to plateau, rapid drop and sharp change to either zero or perhaps negative plateau. I also see a significant difference in the resulting (source) spectrum: the sharp declinations in the square-waved pattern generate greater energy in higher-lying partials, yet I have always understood falsetto to be associated with a high drop-off in energy in the source spectrum. I should add that my understanding (from the related experiences of speech pathologists and from the endoscopies I have seen) is that vocal fold closure can occur in falsetto, at rates related and unrelated the fundamental frequency. One of your replies mentions:
>The spectrum analysis provided by this programme currently in favour
Excuse me if I have missed mention of the program, possibly in the previous discussion which gave rise to this one, but I'm not sure to which program you refer. Without illustration, I am possibly misunderstanding your point completely: perhaps if you were able to send me some of the falsetto source waveforms which you have found to approximate square waveforms, I would understand your concepts better.
Kindest regards
Sally
|