Re: National differences in the tritone paradox

[parncutt@xxxxxxxxxxxxxxxxxxxxx]

On Pierre Divenyi's recommendation, I am forwarding this letter from
John Ohala <ohala@cogsci.berkeley.edu> (with his permission). The
letter begins with a quote from my second letter to the list of
October 30, 1993.

> ... It is clear

> that the timbre, and hence spectral envelope, of specific vowels

> differs from one accent, dialect, or language to another. For

> example, an American "oh" is timbrally deeper than an English "oh",

> suggesting that the American "oh" has a lower centroid frequency.

> Might American vowels be generally (or, at least, on average)

> "timbrally deeper" than English ones? Has anyone measured long-time

> average spectra of the speech of different languages and dialects
to

> find out if there are consistent differences in the distributions?

First, there is someone who has looked at LTAS for different
languages,
but I'm not sure he has included English or dialects of English in
his
survey:  Bernard Harmegnies (Av. de Champ de Mars CH II / Univ de
L'Etat

/ B - 7000 Mons / Belgium; Fax +32 65 373054).  His interest is
voice quality differences between languages.


Second, it is misleading to say that Am. Engl. "oh" is "deeper"
than a Brit. Engl. "oh"; both are diphthongs, the Brit. Engl.
markedly so.  ASCII approximations to an IPA transcription
would give Am. Engl. version as [ow] and Brit-Engl. as
[uh-oo];  since there is no steady-state and both sweep
through the same freq. region, I don't see any possibility of
saying that one is deeper than the other.


Third, in any case, all languages have many vowels which cover
much the same space in acoustic-auditory terms.  With languages that
have front rounded vowels (Fr. [y] as in "tu", [oe] as in "peur")
one might think that they would have more frequencies at the high
end of F2, but as it happens, these vowels are statistically
infrequent in running speech -- so they probably have much the
same distribution of resonant frequencies as other languages.  In

addition the res. freq.'s are constantly changing as a function
of consonants; seldom is a given freq. dwelled on.

Fourth, the actual resonant frequencies of vowels vary with
the size of the vocal tract, being higher for shorter vocal
tracts (female vs. male; children vs. adults).  You might have
a better chance of finding systematically different concentrations
of resonant frequencies if you looked at different sexes
or ages (but then what is important:  the speaker's own
res. freq.'s or those of the people they listen to?).  One might
also find differences as a function of average stature in
diff. countries, e.g., Swedes, Iroquoians, and Watusis vs.

Andean Quechuas, pygmies.  (Assumption:  vocal tract length and
thus res. freq.'s vary inversely with other bodily dimensions.)

The bottom line is that I am extremely skeptical that
language differences would lead to significant differences
in resonant frequencies.

Hope this helps.

John