360 likes | 366 Views
Resonance Lecture 9. Fundamental Frequency (Pitch). 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. Intensity (Loudness).
E N D
Fundamental Frequency (Pitch) • 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
Intensity (Loudness) • 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
Vocal Tract • 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.
Vocal Tract • The vocal folds create the fundamental frequency (“pitch”) • The vocal tract gives us formants (resonances) Titze, I.R. (2000). Principles of Voice Production.
Vocal Tract • 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.
Formants • 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
Nasal Resonance • 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 300-500 Hz
Resonance • 3 Types: • Pharyngeal • Oral • Nasal Zemlin, pg 32.
Resonance • Introduction to vocal tract resonance • Terms and theory • Sound waves • Basics and for speech • Vocal tract formants Zemlin, pg 32.
Vocal Tract • 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.
Vocal Tract • The vocal folds create the fundamental frequency (“pitch”) • The vocal tract gives us formants (resonances) Titze, I.R. (2000). Principles of Voice Production.
Basics of Resonance 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.
Vocal Tract • 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.
Resonances • 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.
Resonance • Introduction to vocal tract resonance • Terms and theory • Sound waves • Basics for speech • Vocal tract formants Zemlin, pg 32.
Mouth Pharynx Glottis Transmitted Reflected Incident Impedance
Standing Waves • N = node • A = antinode • Only occur in the vocal tract at resonant (formant) frequencies
Resonance • Introduction to vocal tract resonance • Terms and theory • Sound waves • Basics for speech • Vocal tract formants Zemlin, pg 32.
Quarter Wavelength Resonator • 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
Formants • 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 Tract: Single Tube • Vocal tracts have more than one resonance (formant) • The following equation is used to find the frequency of a specific formant: Fn = (2n-1)(c/4L) F = formant n = formant number L = vocal tract length
Resonance • Introduction to vocal tract resonance • Terms and theory • Sound waves • Basics for speech • Vocal tract formants Zemlin, pg 32.
Oral Cavity • Lips • Teeth • Tongue • Mandible • Palate • Hard • Soft Zemlin, pg 227.
Lips Innervated by CN VII: Facial Orbicularis oris • Principle muscle acting on the lips • Sphincter (circular) muscle • Contraction: closes and puckers lips Zemlin, pg 234.
Lips • 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 http://en.wikipedia.org/wiki/Buccinator_muscle
Lips • Risorius • Latin risus “laughter” • Parallel to buccinator • Inserts in corners of mouth • Contraction: laterally pulls corners of mouth Zemlin, pg 234.
Lips • 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.
Lips • Zygomatic muscles • Insert into orbicularis oris, including at corners of mouth • Contraction: draws corners of the mouth into a smile Zemlin, pg 234.
Lips Mentalis • Connects the mandible (jaw bone) and chin • Contraction: raises the lower lip, helps with lower lip protrusion Zemlin, pg 234.
Lips 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.
Lips 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.
Hixon, T.J., et al. (2008). Preclinical Speech Science: Anatomy, Physiology, Acoustics, and Perception.