Experimental determinations of the acoustic properties of the subglottal airway, from the trachea below the larynx to the lungs, may provide useful information for detecting airway pathologies and aid in the understanding of vocal fold auto-oscillation. Here, minimally invasive, high precision impedance measurements are made through the lips (7 men, 3 women) over the range 14–4200 Hz during inspiration, expiration, and with a closed glottis. Closed glottis measurements show the expected resonances and anti-resonances of the supraglottal vocal tract. As the glottis is gradually opened, and the glottal inertance decreases, maxima in the subglottal impedance increasingly affect the measured impedance spectrum, producing additional pairs of maxima and minima. The pairs with the lowest frequency appear first. Measurements during a cycle of respiration show the disappearance and reappearance of these extrema. For a wide glottal opening during inspiration, and for the frequency range 14–4200 Hz, the impedance spectrum semi-quantitatively resembles that of a single, longer duct, open at the remote end, and whose total effective length is 37 ± 4 cm for men and 34 ± 3 cm for women. Fitting to simple models of the subglottal tract yields mean effective acoustic lengths of 19.5 cm for the men and 16.0 cm for the women in this study.

1.
Benade
,
A.
(
1985
). “
Air column, reed, and player's windway interaction in musical instruments
,” in
Vocal Fold Physiology, Biomechanics, Acoustics, and Phonatory Control
, edited by
I. R.
Titze
and
R. C.
Scherer
(
Denver Center for the Performing Arts
,
Denver, CO
), Chap. 35, pp.
425
452
.
2.
Brown
,
N. J.
,
Xuan
,
W.
,
Salome
,
C. M.
,
Berend
,
N.
,
Hunter
,
M. L.
,
Musk
,
A.
,
James
,
A. L.
, and
King
,
G. G.
(
2010
). “
Reference equations for respiratory system resistance and reactance in adults
,”
Resp. Physiol. Neurobiol.
172
,
162
168
.
3.
Campbell
,
D.
, and
Brown
,
J.
(
1963
). “
The electrical analogue of lung
,”
British J. Anaesthesia
35
,
684
692
.
4.
Chi
,
X.
, and
Sonderegger
,
M.
(
2007
). “
Subglottal coupling and its influence on vowel formants
,”
J. Acoust. Soc. Am.
122
,
1735
1745
.
5.
Cranen
,
B.
, and
Boves
,
L.
(
1987
). “
On subglottal formant analysis
,”
J. Acoust. Soc. Am.
81
,
734
746
.
6.
Delbridge
,
A.
(
1981
).
The Macquarie Dictionary
(
Macquarie Library, St. Leonards
,
Australia
),
820
pp.
7.
Dickens
,
P.
,
Smith
,
J.
, and
Wolfe
,
J.
(
2007
). “
High precision measurements of acoustic impedance spectra using resonance-free calibration loads and controlled error distribution
,”
J. Acoust. Soc. Am.
121
,
1471
1481
.
8.
Fant
,
G.
,
Ishizaka
,
K.
,
Lindqvist-Gauffin
,
J.
, and
Sundberg
,
J.
(
1972
). “
Subglottal formants
,”
STL-QPSR
13
(
1
),
1
12
.
9.
Fletcher
,
N. H.
(
1993
). “
Autonomous vibration of simple pressure-controlled valves in gas flows
,”
J. Acoust. Soc. Am.
93
,
2172
2180
.
10.
Fredberg
,
J. J.
, and
Hoenig
,
A.
(
1978
). “
Mechanical response of the lungs at high frequencies
,”
J. Biomech. Eng.
100
,
57
66
.
11.
Fujimura
,
O.
, and
Lindqvist
,
J.
(
1971
). “
Sweep-tone measurements of vocal-tract characteristics
,”
J. Acoust. Soc. Am.
49
,
541
558
.
12.
Habib
,
R. H.
,
Chalker
,
R. B.
,
Suki
,
B.
, and
Jackson
,
A. C.
(
1994
). “
Airway geometry and wall mechanical properties estimated from subglottal input impedance in humans
,”
J. Appl. Physiol.
77
,
441
451
.
13.
Hanna
,
N.
(
2014
). “
Investigations of the acoustics of the vocal tract and vocal folds in vivo, ex vivo and in vitro
,”
UNSW, Australia and Université de Grenoble
,
France
,
120
pp.
14.
Hanna
,
N.
,
Amatoury
,
J.
,
Smith
,
J.
, and
Wolfe
,
J.
(
2016b
). “
How long is a vocal tract? Comparison of acoustic impedance spectrometry with magnetic resonance imaging
,”
Proc. Meet. Acoust.
28
,
60001
.
15.
Hanna
,
N.
,
Smith
,
J.
, and
Wolfe
,
J.
(
2012
). “
Low frequency response of the vocal tract: Acoustic and mechanical resonances and their losses
,” in
Proceedings of the Australian Acoustical Society
, edited by
T.
McGinn
,
Fremantle
,
Australia
, pp.
317
323
.
16.
Hanna
,
N.
,
Smith
,
J.
, and
Wolfe
,
J.
(
2016a
). “
Frequencies, bandwidths and magnitudes of vocal tract and surrounding tissue resonances, measured through the lips during phonation
,”
J. Acoust. Soc. Am.
139
,
2924
2936
.
17.
Harper
,
P.
,
Kraman
,
S. S.
,
Pasterkamp
,
H.
, and
Wodicka
,
G. R.
(
2001
). “
An acoustic model of the respiratory tract
,”
IEEE Trans. Biomed. Eng.
48
,
543
550
.
18.
Horsfield
,
K.
,
Dart
,
G.
,
Olson
,
D. E.
,
Filley
,
G. F.
, and
Cumming
,
G.
(
1971
). “
Models of the human bronchial tree
,”
J. Appl. Physiol.
31
,
207
217
.
19.
Ishizaka
,
K.
,
Matsudaira
,
M.
, and
Kaneko
,
T.
(
1976
). “
Input acoustic-impedance measurement of the subglottal system
,”
J. Acoust. Soc. Am.
60
,
190
197
.
20.
Lamarche
,
A.
, and
Ternström
,
S.
(
2008
). “
An exploration of skin acceleration level as a measure of phonatory function in singing
,”
J. Voice
22
,
10
22
.
21.
Lulich
,
S. M.
(
2006
). “
The role of lower airway resonances in defining vowel feature contrasts
,” Ph.D. thesis, Massachusetts Institute of Technology, pp.
32
46
.
22.
Lulich
,
S. M.
(
2010
). “
Subglottal resonances and distinctive features
,”
J. Phonetics
38
,
20
31
.
23.
Lulich
,
S. M.
,
Alwan
,
A.
,
Arsikere
,
H.
,
Morton
,
J. R.
, and
Sommers
,
M. S.
(
2011
). “
Resonances and wave propagation velocity in the subglottal airways
,”
J. Acoust. Soc. Am.
130
,
2108
2115
.
24.
Lulich
,
S. M.
, and
Arsikere
,
H.
(
2015
). “
Tracheo-bronchial soft tissue and cartilage resonances in the subglottal acoustic input impedance
,”
J. Acoust. Soc. Am.
137
,
3436
3446
.
25.
Lulich
,
S. M.
,
Morton
,
J. R.
,
Arsikere
,
H.
,
Sommers
,
M. S.
,
Leung
,
G. K.
, and
Alwan
,
A.
(
2012
). “
Subglottal resonances of adult male and female native speakers of American English
,”
J. Acoust. Soc. Am.
132
,
2592
2602
.
26.
Oostveen
,
E.
,
MacLeod
,
D.
,
Lorino
,
H.
,
Farré
,
R.
,
Hantos
,
Z.
,
Desager
,
K.
, and
Marchal
,
F.
(
2003
). “
The forced oscillation technique in clinical practice: Methodology, recommendations and future developments
,”
Eur. Resp. J.
22
,
1026
1041
.
27.
Robinson
,
P. D.
,
Turner
,
M.
,
Brown
,
N. J.
,
Salome
,
C.
,
Berend
,
N.
,
Marks
,
G. B.
, and
King
,
G. G.
(
2011
). “
Procedures to improve the repeatability of forced oscillation measurements in school-aged children
,”
Resp. Physiol. Neurobiol.
177
,
199
206
.
28.
Smith
,
J. R.
(
1995
). “
Phasing of harmonic components to optimize measured signal-to-noise ratios of transfer-functions
,”
Meas. Sci. Technol.
6
,
1343
1348
.
29.
Smith
,
P. L.
,
Wise
,
R. A.
,
Gold
,
A. R.
,
Schwartz
,
A. R.
, and
Permutt
,
S.
(
1998
). “
Upper airway pressure-flow relationships in obstructive sleep apnea
,”
J. App. Physiol.
64
,
789
795
.
30.
Stevens
,
K. N.
(
2000
).
Acoustic Phonetics
(
MIT Press
,
Cambridge, MA
), pp.
437
440
.
31.
Sundberg
,
J.
,
Scherer
,
R.
,
Hess
,
M.
,
Müller
,
F.
, and
Granqvist
,
S.
(
2013
). “
Subglottal pressure oscillations accompanying phonation
,”
J. Voice
27
,
411
421
.
32.
Titze
,
I. R.
(
2008
). “
Nonlinear source-filter coupling in phonation: Theory
,”
J. Acoust. Soc. Am.
123
,
2733
2749
.
33.
Titze
,
I. R.
,
Baken
,
R. J.
,
Bozeman
,
K. W.
,
Granqvist
,
S.
,
Henrich
,
N.
,
Herbst
,
C. T.
,
Howard
,
D. M.
,
Hunter
,
E. J.
,
Kaelin
,
D.
,
Kent
,
R. D.
,
Kreiman
,
J.
,
Kob
,
M.
,
Löfqvist
,
A.
,
McCoy
,
S.
,
Miller
,
D. G.
,
Noé
,
H.
,
Ronald
,
C.
,
Scherer
,
R. C.
,
Smith
,
J. R.
,
Story
,
B. H.
,
Švec
,
J. G.
,
Ternström
,
S.
, and
Wolfe
,
J.
(
2015
). “
Toward a consensus on symbolic notation of harmonics, resonances, and formants in vocalization
,”
J. Acoust. Soc. Am.
137
(
5
),
3005
3007
.
34.
Titze
,
I. R.
,
Riede
,
T.
, and
Popolo
,
P.
(
2008
). “
Nonlinear source-filter coupling in phonation: Vocal exercises
,”
J. Acoust. Soc. Am.
123
,
1902
1905
.
35.
van den Berg
,
J.
(
1960
). “
An electrical analogue of the trachea, lungs and tissues
,”
Acta Physiol. Pharmacol. Neerlandica.
9
,
361
385
.
36.
Wade
,
L.
,
Hanna
,
N.
,
Smith
,
J.
, and
Wolfe
,
J.
(
2017
). “
The role of vocal tract and subglottal resonances in producing vocal instabilities
,”
J. Acoust. Soc. Am.
141
,
1546
1559
.
37.
Weibel
,
E. R.
(
1963
).
Geometry and Dimensions of Airways of Conductive and Transitory Zones
(
Springer, Berlin
,
Heidelberg
), pp.
110
135
.
38.
Wolfe
,
J.
,
Almeida
,
A.
,
Chen
,
J. M.
,
George
,
D.
,
Hanna
,
N.
, and
Smith
,
J.
(
2013
). “
The player-wind instrument interaction
,” SMAC-2013, Stockholm, pp.
323
330
.
39.
Zañartu
,
M.
,
Mehta
,
D. D.
,
Ho
,
J. C.
,
Wodicka
,
G. R.
, and
Hillman
R. E.
(
2011
). “
Observation and analysis of in vivo vocal fold tissue instabilities produced by nonlinear source-filter coupling: A case study
,”
J. Acoust. Soc. Am.
129
326
339
.
40.
Zhang
,
Z.
,
Neubauer
,
J.
, and
Berry
,
D. A.
(
2006
). “
The influence of sub-glottal acoustics on laboratory models of phonation
,”
J. Acoust. Soc. Am.
120
,
1558
1569
.

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