Pitch changes result from changing the length and tension of the vocal folds The pitch you produce is based on the number of cycles (vocal fold vibrations) per second Hertz (Hz) = cycles/second

Loudness changes result from increasing the length of time that the vocal folds are closed This allows for increased subglottal pressure Laryngeal musculature compresses medially, & larger subglottal pressure is needed to initiate vibration of the vocal folds Doesn’t always change how far the vocal folds move, but affects how the vocal folds come together Softer voice = softer impact Louder voice = harder impact In class DVD example

Length: Women: 14.7 cm Men: 17.5 cm Children: 8.75 cm Can be thought of as a system of tubes Titze, I.R. (2000). Principles of Voice Production.

The vocal folds create the fundamental frequency (“pitch”) The vocal tract gives us formants (resonances) Titze, I.R. (2000). Principles of Voice Production.

Remember from the hearing section: Enhancement of the intensity of a particular frequency component(s) with respect to the intensity of the other components that occurs when its frequency equals or is close to the natural frequency of vibration of an object. Titze, I.R. (2000). Principles of Voice Production.

As the vocal tract lengthens, the formant frequencies decrease Shortening leads to formant frequency increase Lengthening: lower larynx and/or lip rounding Shortening: raising larynx and/or lip retracting

For nasal sounds (m, n, ng) and nasalized vowels, the soft palate is lowered Allows air to enter the nasal cavity This adds an extra formant Usually between Hz

3 Types: Pharyngeal Oral Nasal Zemlin, pg 32.

Introduction to vocal tract resonance Terms and theory Sound waves Basics and for speech Vocal tract formants Zemlin, pg 32.

Length: Women: 14.7 cm Men: 17.5 cm Children: 8.75 cm Can be thought of as a system of tubes Titze, I.R. (2000). Principles of Voice Production.

The vocal folds create the fundamental frequency (“pitch”) The vocal tract gives us formants (resonances) Titze, I.R. (2000). Principles of Voice Production.

Source-Filter Theory of Voice Production Source = vocal folds (glottis) Filter = vocal tract (pharynx/oral cavity) “Whereas the glottis produces a sound of many frequencies, the vocal tract selects (filters) a subset of these frequencies for radiation from the mouth.” Note: This theory states that the vocal folds produce the fundamental frequency (pitch)- the vocal tract does not change the pitch Quote from: Titze, I.R. (2000). Principles of Voice Production.

Resonance: Enhancement of the intensity of a particular frequency component(s) with respect to the intensity of the other components that occurs when its frequency equals or is close to the natural frequency of vibration of an object. Formant: A resonance of the vocal tract Titze, I.R. (2000). Principles of Voice Production.

Remember from hearing physiology: Resonance of ear canal: Around 2.5 kHz Resonance of the concha: Around 5 kHz The vocal tract also has multiple resonances (formants) When talking about vowels, we usually discuss the first 2-3 formants, which vary based on the speech sound being produced Quote from: Titze, I.R. (2000). Principles of Voice Production.

Introduction to vocal tract resonance Terms and theory Sound waves Basics for speech Vocal tract formants Zemlin, pg 32.

GlottisMouth ReflectedIncidentTransmitted Pharynx Impedance

N = node A = antinode Only occur in the vocal tract at resonant (formant) frequencies

Introduction to vocal tract resonance Terms and theory Sound waves Basics for speech Vocal tract formants Zemlin, pg 32.

4 x length of vocal tract = wavelength of the formant This equation works for the first formant λ = c/f f = c/λ f = c/(4L) λ = wavelength c = 340 m/s (34,000 cm/s) f = frequency L = vocal tract length

As the vocal tract lengthens, the formant frequencies decrease Shortening leads to an increase in formant frequencies Some ways you can influence vocal tract length: Lengthening: lowering larynx and/or lip rounding Shortening: raising larynx and/or lip retracting Your book states that the larynx can be raised or lowered by as much as 2 cm

Vocal tracts have more than one resonance (formant) The following equation is used to find the frequency of a specific formant: F n = (2n-1)(c/4L) F = formant n = formant number L = vocal tract length

Introduction to vocal tract resonance Terms and theory Sound waves Basics for speech Vocal tract formants Zemlin, pg 32.

Lips Teeth Tongue Mandible Palate Hard Soft Zemlin, pg 227.

Innervated by CN VII: Facial Orbicularis oris Principle muscle acting on the lips Sphincter (circular) muscle Contraction: closes and puckers lips Zemlin, pg 234.

Buccinator Principle muscle of the cheeks Inserts into the corners of the mouth Contraction: compresses the lips and cheeks against the teeth, laterally pulls corners of mouth

Risorius Latin risus “laughter” Parallel to buccinator Inserts in corners of mouth Contraction: laterally pulls corners of mouth Zemlin, pg 234.

Labii Levator labii Insert into the upper lip Contraction: elevate upper lip Depressor labii Inserts into lower lip Contraction: pulls lower lip down Zemlin, pg 234.

Zygomatic muscles Insert into orbicularis oris, including at corners of mouth Contraction: draws corners of the mouth into a smile Zemlin, pg 234.

Mentalis Connects the mandible (jaw bone) and chin Contraction: raises the lower lip, helps with lower lip protrusion Zemlin, pg 234.

Anguli oris Levator anguli oris Insert: both upper and lower lips Contraction: draws corners of the mouth upward, helps close mouth by drawing lower lip up Depressor anguli oris Insert: orbicularis oris, mouth angles Contraction: draws corners of the mouth downward, helps close mouth by drawing upper lip down Zemlin, pg 234.

Incisivus labii Incisivus labii superior Insert: corners of lips Contraction: puckers lips pulling corners of mouth up and inward Incisivus labii inferior Insert: orbicularis oris, mouth angles Contraction: puckers lips pulling corners of mouth down and inward Hixon, T.J., et al. (2008). Preclinical Speech Science: Anatomy, Physiology, Acoustics, and Perception.