1. Speech Science Fall 2009 Oct 26, 2009

2. Consonants Resonant Consonants They are produced in a similar way as vowels i.e., filtering the complex wave produced at the glottis in the resonating cavities of the vocal tract. The Semivowels glides (/w/ and /j/) and liquids (/r/ and /l/) The Nasals /m/, /n/, and [ŋ] Mining [maInIŋ]

3. Consonants Nasals Velopharyngeal port Opening to the nasal cavity from the pharyngeal and oral cavities. This must be opened for the three nasal sounds. It is closed by elevating and backing the velum.

4. Consonants Nonresonant Consonants: They are produced by articulators forming constrictions and occlusions within the vocal tract that generate aperiodic noise as air passes through them. Much more restricted airflow than that for the semivowels and nasals. Acoustically, unlike vowels and resonant consonants, they display no formant structure. The Fricatives, The Stops, The Affricates

5. Consonants The Stops: Airflow in vocal tract is blocked completely for a brief period of time and then the built up air pressure is released suddenly. /p/, /t/, /k/ Other name for these sounds is “plosives” http://home.hib.no/al/engelsk/seksjon/SOFF- MASTER/Stops.htm http://home.hib.no/al/engelsk/seksjon/SOFF- MASTER/Stops.htm

6. Consonants The Fricatives An aperiodic sound is produced by forcing the air stream through an articulatory constriction for relatively extended period of time. This will cause a continuous source of noise that is longer in duration than the transient noise bursts of the stops. http://home.hib.no/al/engelsk/seksjo n/SOFF-MASTER/Fricatives.htm http://home.hib.no/al/engelsk/seksjo n/SOFF-MASTER/Fricatives.htm

7. Consonants The Affricates An affricate is simply a stop with a fricative release [t ʃ ] and [d ʒ ]

8. Consonants: Types of Sound Sources

9. Acoustics of the Semivowels There are similarities between vowels and liquids and glides Vocal tract is relatively open for the semivowels. Acoustically, they are characterized by the formants.

10. Acoustics of the Semivowels /j/ For the production of /j/, tongue blade must approximate the palate at a position close to that for a high front vowel /aja/ The first formant frequency decreases Second formant frequency increases Movement of the tongue and lips change vocal tract shape from starting position (similar to /i/) to next vowel sound.

11. Acoustics of the Semivowels /w/ Starting position is characterized by a high back tongue position and protruded lips (similar to /u/). The articulators then move rapidly to following vowel.

12. Acoustics of the Semivowels /r/ and /l/ They are produced in syllable-initial position by raising the tongue toward the alveolar ridge. Tongue tip position and configuration creates distinction between these two sounds

13. Acoustics of the Semivowels For /r/, F3 frequency plunges below the F3 frequencies of neighboring vowels For /l/, it doesn’t depart from them significantly.

14. Acoustics of the Semivowels /l/ and /r/ in their final position Final /l/ is articulated with the dorsum of the tongue raised somewhat toward the velum (e.g., cool, full) For final /r/, loses its consonantal quality and simply colors whatever vowel it follows. (e.g., car and hear Some speakers may elevate the tongue dorsum toward the palate.

15. Acoustics of the Nasals The addition of nasal cavity creates vocal tract a longer and larger resonator. Therefore, it naturally responds to lower frequencies. Acoustic result is called “murmur” This murmur or formant lies within the 200-300 Hz range Acoustically, nasal consonants are weak due to antiresonances within the vocal tract.

16. Acoustics of the Nasals The antiresonances are frequency regions in which the amplitudes of the source components are severely attenuated. Consonants are articulated with more constriction or occlusions than vowels. Resonances and antiresonances can cancel each other if those frequencies are close enough or one formant may appear as two.

17. Acoustics of the Nasals The frequency ranges for the antiresonances associated with nasal sounds vary with place of articulation. For /m/, antiresonance is in the range of 500-1500 Hz. For /n/, the range is between 2000-3000 Hz and for / /, it is above 3000 Hz.