Approximents Flashcards
What are approximants?
Approximants are speech sounds that involve the articulators approaching each other but not narrowly enough or with enough articulatory precision to create turbulent airflow. They can be classified as liquids or glides, central and lateral
Give examples of approximants in English.
In english the approximants are /j,w,r,l/ other languages have other approximants such as the lateral retroflex approximant /ɭ/ found in rural dialects of punjabi.
Approximants are produced through two processes. What are they and how do they differ?
1.)Glides
Produced with a constriction that is not sufficiently narrow to cause a significant average pressure drop across the constriction during normal voicing
Similar that of nasals as both produced with little or no pressure drop in the airways above glottis, however- the oral cavity is OPEN in glides- air flows past a constriction in the vocal tract.
2.)Liquids
Differ from glides in that the constriction is shorter than that produced with the tongue blade or with the tongue body and rounded lips for the glides.
What are the 2 similarities in the acoustic features of approximants and their cognate high vowels /i, u/
- ) acoustic properties of approximants are quite similar to those of vowels produced at a comparable location in the vocal tract.
- ) Production of labial velar approximant [w] the back of the tongue is brought closer to the velum and the lips are rounded. Similar to the production of [u] F1 and F2 low and close together whilst F3 remains as a steady 2,300 Hz (approx)
What are the 3 differences in the acoustic features of approximants and their cognate high vowels /i, u/
- ) Greater degree of constriction in the vocal tract than cognate vowels.
- ) Their formant pattern - it is clear but weaker than for the vowels because they have a slightly greater constriction, which results in a shorter steady -state position and lower acoustic energy. E.g [j] has the blade of the tongue positioned relatively close to the palate, similar to that of the vowel [i] main difference being that the blade is closer to the palate for [j] then for [i] but [j] is less intense due to the airflow being impeded.
- ) longer formant transition durations than vowels
Why does the retroflex approximant have a low F3 Frequency?
Because the lip rounding, narrowing near the alveolar ridge and the narrowing in the pharynx all play a role in closing the F3 to the F2 frequency gap. The retroflex approximant has the lowest F3 in all speech sounds - dipping below 2,000 Hz even in females.
Explain how glides are articulated.
Glides stand for the gradual articulatory motions that characterise these sound. Articulatory motion slow compared to stops and nasals. These consonants have a markedly narrow, but not closed vocal tract.
For /w/, which there two areas are narrowed?
- ) At the lips
2. ) Between the liguo dorsum and the velum
What is the frequency when producing a glide?
It has a Low frequency where the velar and labial constrictions are what contribute to the lowering of F1. F1 = around 260 Hz.
What is the first formant frequency when producing a glide?
It has a low first formant where the glides /w/ and /j/ are produced with a narrowing in the oral cavity that is more constricted than from a high vowel. This leads to a low first formant frequency (250-300 Hz) with the constriction not sufficiently small that it produces turbulence noise at the constriction.
What is the rate of constriction when producing a glide?
It is considerably slower in glides than that for a stop consonant.For [w] the tongue body and lop constructions lead to F2 below 1000 hz and relatively wide band width. For [j] the long palatal constriction for the glide gives rise to high frequency F2, F3.
[w]+ vowel transition is slower than that of a plosive vowel transition but not as much as that of a vowel-vowel transition.
What does Leiberman et al (1956) tell us about the duration of transition?
the duration of transition accounted for listener responses to phonetic contrasts : e.g when transition duration was shorter than about 40-60 msecs listeners tended to hear a stop consonant. When the transition was greater than 49-60 ms but less than 100-150 msecs then listeners judged the sound to be a glide.
Explain how liquids are articulated.
The liquids /r/ and /l/ considered are produced by raising the tongue blade to form a narrowing of the airway in the region of the hard palate.Liquids are produced with little or no pressure increase behind the constriction and with continuous glottal vibration (like glides).The vocal tract configuration for /l/ has a complete midline closure of the tongue blade.The blade is shaped so that the main airway passes around its lateral edge and a side branch of this airway is formed on the midline.
How does the movement of /r/ and /l/ differ from /j/ and /w/ ?
The articulation movements for /r/ nd /l/ is quite rapid.
What is different about the F1 in liquids as opposed to the F1 in glides?
Liquids have a higher F1 than glides
