The Flow and Pressure Relationships in Different Tubes Commonly Used for Semi-occluded Vocal Tract Exercises


      This experimental study investigated the back pressure (Pback) versus flow (U) relationship for 10 different tubes commonly used for semi-occluded vocal tract exercises, that is, eight straws of different lengths and diameters, a resonance tube, and a silicone tube similar to a Lax Vox tube. All tubes were assessed with the free end in air. The resonance tube and silicone tube were further assessed with the free end under water at the depths from 1 to 7 cm in steps of 1 cm. The results showed that relative changes in the diameter of straws affect Pback considerably more compared with the same amount of relative change in length. Additionally, once tubes are submerged into water, Pback needs to overcome the pressure generated by the water depth before flow can start. Under this condition, only a small increase in Pback was observed as the flow was increased. Therefore, the wider tubes submerged into water produced an almost constant Pback determined by the water depth, whereas the thinner straws in air produced relatively large changes to Pback as flow was changed. These differences may be taken advantage of when customizing exercises for different users and diagnoses and optimizing the therapy outcome.

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        • Story B.H.
        • Laukkanen A.-M.
        • Titze I.R.
        Acoustic impedance of an artificially lengthened and constricted vocal tract.
        J Voice. 2000; 14: 455-469
        • Linklater K.
        Freeing the Natural Voice.
        Drama Book, New York, NY1976
        • Nix J.
        Lip trills and raspberries: “High spit factor” alternatives to the nasal continuant consonants.
        J Sing. 1999; 55: 15-19
        • Aderhold E.
        Sprecherziehung des Schauspielers: Grundlagen und Methoden.
        Henschel Verlag, Berlin, Germany1963
        • Coffin B.
        Coffin's Sound of Singing. Principles and Applications of Vocal Techniques With Chromatic Vowel Chart.
        2nd ed. Scarecrow Press, Metuchen, NJ1987
        • Sovijarvi A.
        Die bestimmung der stimmkategorien mittels resonanzröhren.
        in: Fifth International Congress of Phonetic Sciences. Karger, Basel, NY1965
        • Simberg S.
        • Laine A.
        The resonance tube method in voice therapy: description and practical implementations.
        Logoped Phoniatr Vocol. 2007; 32: 165-170
        • Denizoglu I.
        The LaxVox voice therapy: method and applications.
        Turkiye Klinikleri JENT Spec Top. 2013; 6: 32-40
        • Enflo L.
        Collision Threshold Pressure: A Novel Measure of Voice Function—Effect of Vocal Warm-Up, Vocal Loading and Resonance Tube Phonation in Water.
        Division of Speech and Language Pathology, Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden2013
        • Granqvist S.
        • Simberg S.
        • Hertegard S.
        • et al.
        Resonance tube phonation in water: high-speed imaging, electroglottographic and oral pressure observations of vocal fold vibrations—a pilot study.
        Logoped Phoniatr Vocol. 2014; : 1-9
        • Titze I.R.
        • Story B.H.
        Acoustic interactions of the voice source with the lower vocal tract.
        J Acoust Soc Am. 1997; 101: 2234-2243
        • Titze I.R.
        Voice training and therapy with a semi-occluded vocal tract: rationale and scientific underpinnings.
        J Speech Hear Res. 2006; 49: 448-459
        • Laukkanen A.-M.
        • Titze I.R.
        • Hoffman H.
        • Finnegan E.
        Effects of a semioccluded vocal tract on laryngeal muscle activity and glottal adduction in a single female subject.
        Folia Phoniatr Logop. 2008; 60: 298-311
        • Vampola T.
        • Laukkanen A.-M.
        • Horáček J.
        • Švec J.G.
        Vocal tract changes caused by phonation into a tube: a case study using computer tomography and finite-element modeling.
        J Acoust Soc Am. 2011; 129: 310-315
        • Guzman M.
        • Laukkanen A.-M.
        • Krupa P.
        • Horacek J.
        • Svec J.G.
        • Geneid A.
        Vocal tract and glottal function during and after vocal exercising with resonance tube and straw.
        J Voice. 2013; 27: 523.e19-523.e34
        • Laukkanen A.-M.
        • Horáček J.
        • Krupa P.
        • Švec J.G.
        The effect of phonation into a straw on the vocal tract adjustments and formant frequencies. A preliminary MRI study on a single subject completed with acoustic results.
        Biomed Signal Process Control. 2012; 7: 50-57
        • Guzmán M.
        • Castro C.
        • Testart A.
        • Munoz D.
        • Gerhard J.
        Laryngeal and pharyngeal activity during semioccluded vocal tract postures in subjects diagnosed with hyperfunctional dysphonia.
        J Voice. 2013; 27: 709-716
        • Amarante Andrade P.
        • Wood G.
        • Ratcliffe P.
        • Epstein R.
        • Pijper A.
        • Svec J.G.
        Electroglottographic study of seven semi-occluded exercises: LaxVox, straw, lip-trill, tongue-trill, humming, hand-over-mouth, and tongue-trill combined with hand-over-mouth.
        J Voice. 2014; 28: 589-595
      1. Radolf V, Laukkanen A-M, Horacek J, Vesely J, Liu D. In vivo measurements of air pressure, vocal folds vibration and acoustic characteristics of phonation into a straw and a resonance tube used in vocal exercising. Paper presented at: 19th International Conference Engineering Mechanics 2013; [Czech Republic].

        • Maxfield L.
        • Titze I.
        • Hunter E.
        • Kapsner-Smith M.
        Intraoral pressures produced by thirteen semi-occluded vocal tract gestures.
        Logoped Phoniatr Vocol. 2014; : 1-7
        • Baken R.J.
        • Orlikoff R.F.
        Clinical Measurements of Speech and Voice.
        Singular Publishing Group, San Diego, CA2000
        • Nakayama Y.
        • Boucher R.
        Introduction to Fluid Mechanics.
        Butterworth-Heinemann, Oxford, UK1998
        • Titze I.R.
        • Finnegan E.
        • Laukkanen A.-M.
        • Jaiswal S.
        Raising lung pressure and pitch in vocal warm-ups: the use of flow-resistant straws.
        J Sing. 2002; 58: 329-338
        • Adams J.A.
        A closed-loop theory of motor learning.
        J Mot Behav. 1971; 3: 111-150