In a message dated 8/1/2000 5:10:43 PM, etan@...
>Do these formants stay constant regardless of pitch, or are they
>relative to pitch? -Nate
Since I didn't see an answer to this, I'll just ramble on -- especially with
the list so quiet. Yes Nate, these would change relative to pitch. I find
formants get way too much press amongst EM users since they are so closely
related to the kinds of stuff that we know (frequencies, spectrograms,
resonance). These are a very small part of phonetics since they really only
relate to vowels, but they're cool because you can study them empirically.
Some (hopefully) interesting excerpts about formants from Peter Laderfoged's
book "A Course in Phonetics" 2nd edition 1982:
"In the first part of this chapter I described how differences in pitch and
loudness can be recorded. Now we must consider the differences in quality. A
set of vowel sounds provides a suitable starting point, since vowels can all
be said on the same pitch and with the same loudness.
"The quality of a sound such as a vowel depends upon its overtone structure.
Putting it another way, we can say that a vowel sound contains a number of
different pitches simultaneously. There is the pitch at which it is actually
spoken, and there are the various overtone pitches that give it its
distinctive quality. We distinguish one vowel from another by the differences
in the overtones that are audible.
"Normally, one cannot hear the separate overtones of a vowel as
distinguishable pitches. The only sensation of pitch is the note on which the
vowel said, which depends on the rate of vibration (the frequency) of the
vocal cords. But there are circumstances in which the characteristic overtone
structure of each vowel can be heard. Try saying the vowels" [sorry, I don't
know how to get this keyboard to produce the International Phonetic Alphabet]
"as in the words 'heed, hid, head, had, hod, hawed, hood, who'd.' Now whisper
these vowels. In a whispered sound the vocal cords are not vibrating, and
there is no regular pitch of the voice. Nevertheless, when you whisper these
vowels you can hear that they form a series of sounds on a continuously
descending pitch. What you are hearing is one of the overtones that
characterize the vowels. This particular overtone is highest for [i] and
lowest for [u], with the other words in the series being in between. Now try
whistling a very high note, and then the lowest note that you can. You will
find that for the high note you have your tongue in the position for [i] --
but of course with the lips rounded, as in the vowel in the French word 'tu'
-- and for the low note your lips and tongue are in the [u] position. Again,
intermediate notes would have the tongue positions of the other vowels in the
And of course [i] is the IPA spelling for the vowel sound in "heed" while [u]
is the vowel sound in "who'd."
Now back to MTOM speak!
>Paul Schreiber wrote:
>> (Vowel Sound/First Formant/Second/Third) Freq in Hz.
>> >From ancient Bell Labs stuff.