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From:  "Lloyd W. Hanson" <lloyd.hanson@n...>
"Lloyd W. Hanson" <lloyd.hanson@n...>
Date:  Sun Jan 21, 2001  6:23 am
Subject:  Re: Velum/Spec analysis/Nasal Res........


Dear Vocalisters

It is very easy to assume that the air which passes through the glottis is
the vehicle that carries the vocal tone out into the world. Nothing could
be further from the truth.

The vocal folds are set in motion by the air pressure under the folds
(glottis) which is intense enough to force open the folds. The folds then
are closed by a combination of the natural muscle elasticity of the folds
together with the Bernoulli effect as the air passing over the folds
increases in velocity, and the inertance of the air in the vocal tract
which acts as a kind of pneumatic spring. The effect of all this is a
consistent oscillation of the vocal folds which creates a vibratory pattern
in the vocal tract.

Sound is transmitted as the molecules of air transmit their vibratory energy
(kinetic energy) from one to another. Each molecule moves backward and
forward but the air molecules do not move forward in a continuous line,
that is, the air does not move forward as in a breeze. Sound is
transmitted through the air in this transfer of energy method whether the
air is in the mouth or in the room. Breath energy's only function is to
create an oscillation of the vocal folds such that the vocal folds
establish a vibratory pattern in the air molecules.

For this reason, the opening of the nasal port will have no or very little
effect on the amount of air necessary to sing. A nasal tone requires no
more use of air than a non-nasal tone. The use of air (breath) is only to
maintain the oscillation of the vocal folds, not the transmission of sound.

To the extent that the nasal port is open, to that extent the nasal cavity
will become a side branch resonator which creates a resonance that tends to
muffle the tone being transmitted through the mouth cavity. It is possible
to use the nasal cavity as the primary resonance cavity but the tone so
produced is not consider valid in classical western singing. In much
eastern music it is considered as a desirable quality

It is possible to open the nasal port slightly and reduce the effect of the
nasal area acting as a side branch resonator. It is also possible that
many singers consider this a more comfortable way to produce a tone because
it feels more resonant. I have also had students who reduce the resonance
in their mouth cavity when they completely close the nasal port but this
has usually been caused by additional tension in the pharyngeal area as
they struggle to reduce nasal resonance, especially if nasal resonance has
been a primary part of their singing habit.

The soft palate area can be lifted even if the nasal port is slightly open.
The soft palate area can also be lowered even if the nasal port is closed.
The nasal port and the soft palate occupy much of the same area in the
mouth but they are not two terms for the same thing. It is also true that
any lifting of the soft palate will lower the larynx. The muscle systems
which affect the soft palate and the larynx work in opposite directions.

It is the adjustments of the total of the vocal tract (pharynx, mouth,
tongue, soft palate, etc.) that effects vowel pronunciation. These
adjustments change the vowel sound whether speaking or singing. Any tonal
color use in singing is nothing more than a change in vowel pronunciation.
Vocal "cover", for example, is merely an alteration of vowel pronunciation.
All of these changes in vowel pronunciation (or tonal changes, if you
prefer) occur because the infinite volume and shape adjustments possible in
the vocal tract also create different resonance characteristics within the
vocal tract. These resonance characteristics are called vowel formants.

Given this flexibility it is not surprising that there is more than one
adjustment possible for similar vowel sounds. And if one adds to this the
fact that each singer has a different size (volume) and shaped vocal tract
it becomes obvious that only generalities can be established about
necessary vocal tract configurations between singers.

It is often difficult to maintain a coordination of the many knowledges we
learn about the voice but it is necessary to do so. When one bit of
information appears to contradict another it is natural to return to a
subjective approach to understand vocal function but this is a mistake. It
is best to assume that there is other information we must learn and
understand which will assist us to connect our previously learned material
with newer material that appears to be contradictive.

The primary function of subjectivity in singing is in interpretation and the
expression of emotion. Subjectivity is necessary and singing has no
meaning without it but subjectivity is of little value as a tool to explain
the function of the vocal instrument.


Regards
--
Lloyd W. Hanson, DMA
Professor of Voice, Vocal Pedagogy
School of Performing Arts
Northern Arizona University
Flagstaff, AZ 86011



  Replies Name/Email Yahoo! ID Date Size
8578 Re: Velum/Spec analysis/Nasal Res........ Reg Boyle   Sun  1/21/2001   3 KB
8585 Re: Velum/Spec analysis/Nasal Res........ Lloyd W. Hanson   Sun  1/21/2001   4 KB
8595 Re: Velum/Spec analysis/Nasal Res........ Reg Boyle   Sun  1/21/2001   3 KB
8596 Re: Velum/Spec analysis/Nasal Res........again taylor23f@h...   Sun  1/21/2001   3 KB

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