Part 1: Acoustic Phonetics Data Flashcards

Question

Constriction Interval

Answer 1

interval of relatively “flat” formants assumed to correspond to the part of semivowel articulation when the vocal tract is most constricted formant pattern like those of vowels

Answer 2

pattern of formant transitions into and out of the constriction intervals also distinguishes among the semivowels Important characteristics (see 11-9) the specific formants that have large transitions into and out of the constriction interval the direction (rising versus falling) of the transitions

Answer 3

semivowel errors are frequent during phonological development and in speech delay E.g., /w/ for /ɹ/, /w/ for /l/, and /j/ for /l/ Need to determine if the issue is due to articulatory control needed to differentiate the sounds or distinguishing the perceptual representations

Answer 4

the acoustics of a [w] in a [w] for /ɹ/ error (or any other substitution error) are often not like the acoustics of normally articulated [w] the error [w] is different from correct [w] by having acoustic characteristics more or less between the error sound and the correct sound This shows that the child hears the difference but has difficulty with articulation A distinction is made by the child but may be too subtle for human listeners to perceive. Even if listeners do hear a subtle distinction they may place it in a “comfortable” phoneme category

Answer 5

Challenging to segment semivowels from adjacent vowels When constriction intervals can be segmented from the surrounding transitions they have durations of 30 to 70 ms, with the majority of values toward the lower end of this range

Answer 6

Combined duration of the transition and constriction intervals of semivowels may be brief (as short as 100 ms) Suggests rapid, complex articulatory gestures occurring in a short amount of time--may explain, in part, why children master the contrasts of these sounds relatively late in the overall scheme of phonological development

Answer 7

Characterized by an interval of aperiodic energy whose spectrum and overall amplitude depend on place of articulation and, in some cases, voicing status. In English, fricatives are categorized as sibilants (/s, z,ʃ,ʒ/), nonsibilants (/f, v,θ,ð/), and the glottal fricative /h/

Answer 8

Sibilants are more intense and have better-defined spectra than nonsibilants. Sibilants have more easily identified spectral peaks and concentrations of spectral energy

Answer 9

The intensity difference is represented in the spectrogram by the much darker frication noise Overall higher level of /s/ compared with /f/ This intensity difference is consistent for any sibilant-nonsibilant comparison Higher intensity for sibilants is largely due to an obstacle (i.e., teeth) in the path of the airstream Sibilants typically have peakier spectra than nonsibilants /f/ spectrum is flatter than the /s/ spectrum

Answer 10

The “peak frequency” does not consider additional information in fricative spectra. Varying shapes Spectral moments: four numbers that represent the spectral shape basic statistical properties of a distribution of numbers, applied to speech-sound spectra

Answer 11

Evidence for the importance of formant transitions in distinguishing place of articulation for nonsibilant fricatives is mixed. Jongman et al. (2000) failed to identify formant transition patterns that consistently separated the four places of fricative articulation

Answer 12

voiceless fricatives are longer than voiced fricatives Other factors can influence duration Position-in-word Stress level of the syllable Speaking rate Phonetic context Sibilants are longer than nonsibilants

Answer 13

Voiceless fricatives require the laryngeal devoicing gesture (LDG), an opening-closing movement of the vocal folds observed for voiceless obstruents The opening plus closing motions of the LDG produce a very long event compared to the short-duration opening and closing motions of a single cycle of vocal fold vibration. The LDG typically has a duration of roughly 120 to 150 ms, whereas an example of a “long” period for one phonatory cycle would be roughly 10 ms

Answer 14

glottis is partially or largely open and the aperiodic source is produced when the air jet emerging from the constriction between the vocal folds strikes the edges of the ventricular folds and epiglottis, generating turbulent airflow

Answer 15

/h/-interval contains aperiodic energy Intervocalic /h/ often has a combination of aperiodic and weak, periodic energy suggesting that the abducted vocal folds are vibrating loosely, with minimal or absent closed phases

Answer 16

Formants can be detected during the /h/-intervals /h/ is produced with the vocal tract shape of the surrounding vowel(s) Relative weakness of energy around F1 compared with the much more intense energy of the upper formants Due to sound absorption in the trachea Loss of F1 energy resulting from vocal fold vibration in which there is poor closure Explains intelligibility problems due to indistinct vowels in people with breathy voice

Answer 17

Only consonant type to occur in virtually all languages of the world Among the most frequently occurring consonant segments

Answer 18

Closure interval and burst are acoustic markers of stop consonants Closure interval corresponds to the interval during which the vocal tract is completely sealed Closure intervals for voiceless stops appear as white intervals on spectrograms Closure interval is white with periodic energy along the baseline indicating vibration of the vocal folds for voiced stops

Answer 19

In connected speech, closure intervals for any of the stop consonants are rarely greater than 70 ms, the majority having durations of around 60 ms In more formal utterances, the values are often longer than 70 ms but rarely exceed 100 ms

Answer 20

Claims that stop closure durations are longer for voiceless compared with voiced stops Claims that durations become increasingly shorter as place of articulation moves back in the vocal tract (i.e., /p/ closures are longer than /t/, and, are longer than /k/) Inconsistency in research regarding stop closure durations (Table 11-6)

Answer 21

Voiceless stop closure durations between 2 and 6 ms longer than voiced stops in connected speech Difference of insufficient magnitude to serve as a useful perceptual cue to the voicing status of a stop.

Answer 22

t/ and /d/ in the intervocalic, post-stressed position of words (e.g., butter, matter, ruder) Shorter than stop closures in more formal speech styles

Answer 23

Tendency for labials to have the longest durations Differences between lingua-alveolar and dorsal closure durations are less clear

Answer 24

Acoustics of stop consonant voicing are complex Cues that signal the voicing status of a stop are context dependent absence of glottal pulses during a voiceless closure interval is almost always the case, but glottal pulses do not always occur throughout the entire closure interval of a voiced stop

Answer 25

Without other potential cues for the stop voicing distinction, voiced stops may be considered more vulnerable to perceptual errors compared with voiceless stops Speakers with speech motor control problems (e.g., apraxia, dysarthria) more often produce voiceless-for-voiced than voiced-for-voiceless errors

Answer 26

LDG explains the absence of glottal pulses within the stop closure interval Synchronized onsets of the LDG and supralaryngeal closure LDG duration of well over 100 ms for stops (see Figure 11-29) Release of the stop consonant closure interval roughly 60 to 70 ms after its onset (compared with the fricative constriction over the entire duration of the LDG )

Answer 27

Voiced stops do not have an LDG During the closure interval, the vocal folds remain in the midline, phonation-ready position The value of VOT is grossly correlated with the presence versus absence of glottal pulses within a stop closure interval. positive and negative VOT values are common for voiced stops

Answer 28

Value of VOT can generally be used as a correlate of the voicing status of a stop consonant “Mismatches” between VOT values and the voicing status for stops usually occur only when voiceless stops have a VOT in the short-lag range. Voiceless stops in the post-stressed position of a word Voiceless stop is part of an s + stop cluster within a single syllable

Answer 29

Many languages have stop voicing distinctions, but divide the VOT range in different ways compared with English. different languages exploit the VOT continuum to “implement” their unique voicing contrasts Korean has a three-way voicing distinction for each place of articulation French has a two-way voicing contrast but divides the VOT continuum differently than English Voiced stops of French all have negative VOTs (i.e., they are prevoiced), and short-lag, positive VOTs for voiceless stops

Answer 30

Spectra for burst sources and frication sources are similar even though their aeromechanics are different Both source spectra are shaped significantly by the resonator in front of the source

Answer 31

Considered one of the hallmarks of the stop manner of production However, many stop consonants have no identifiable burst in connected speech

Answer 32

Labial bursts: primary concentration of energy in the lower frequencies Lingua-alveolar: flat spectra or an emphasis of energy in the high frequencies (above 4.0 kHz) Dorsal stops: prominent energy peaks in the midfrequency regions, roughly between 1.5 and 4.0 kHz.

Answer 33

Characteristics that are always found in the spectrum, or the manner in which the spectrum changes as a function of time, regardless of who is producing the utterance or under what conditions the utterance is spoken. complicated by the phenomenon of coarticulation

Answer 34

Influence of one segment on another Articulatory (and acoustic) characteristics of a speech sound segment depend on the articulatory (acoustic) characteristics of adjacent, and in some cases nonadjacent, segments

Answer 35

Vowel-induced variation could result in highly variable stop burst spectra for a given place of articulation Too little acoustic stability to serve as a reliable cue to place identification.

Answer 36

The auditory system may strip away spectral detail and use the gross spectral shape to identify stop place of articulation. Blumstein and Stevens (1979) described spectral shapes for the three different places of stop articulation. diffuse-falling for bilabials diffuse-rising for lingua-alveolars compact for dorsals

Answer 37

Early perceptual experiments resulted in a conclusion of “no acoustic invariance” for stop consonants Haskins scientists found they could elicit perception of a stop-vowel syllable with a pattern having only F1-F2 transitions and the steady states of the following vowel burst was not necessary for perception of a stop consonant

Answer 38

Because vowel context had such influence on acoustic characteristics of stop consonants, Haskins scientists argued that there was no acoustic invariance for the place feature of stop consonants. Led to a theory of speech perception that downplays (if not eliminates) a primary role for auditory acoustic analysis in the perception of speech

Answer 39

Blumstein and Stevens (1979), and others, had success in classifying stop place of articulation using the burst spectrum Ability to assign 85% to 95% of burst spectra to the “correct” place of articulation pointed to sufficient acoustic invariance for stop consonants

Answer 40

Regression equations that combines measures reflecting both consonant and vowel production Developed by Sussman, Lindblom et. al

Answer 41

Acoustic characteristics vary for many reasons related to the speaker and conditions Age Dialect Sex Size Phonetic context Speaking rate Speaking style If the acoustic characteristics of a speech sound are so variable, exactly what is meant by the term “acoustic invariance”?

Answer 42

Haskins scientists had a stricter interpretations virtually no acoustic variability Blumstein & Stevens (1979) and others had a looser approach Allowed that a sufficient degree of acoustic invariance was demonstrated according to their analysis criteria Lindblom (1990) said the issue is how much acoustic characteristics can vary and still remain distinctive relative to neighboring sounds.

Answer 43

Frication interval of the English affricates /tʃ/ and /d3/ is longer than the frication interval of the stop component and shorter than the typical duration of the fricative component Stop closure duration of affricates tends to be slightly shorter than the closure duration of singleton stops

Answer 44

Place of articulation of the English affricates is slightly posterior to the place of articulation for lingua-alveolar stops and fricatives Place of articulation of the English affricates is slightly posterior to the place of articulation for lingua-alveolar stops and fricatives

Answer 45

Intonation Rhythm Stress Pause Grammatical function

Answer 46

For declarative phrases, an F0 peak typically occurs near the beginning of the phrase, followed by a gradually declining F0 to the lowest value at the end of the phrase An interrogative F0 contour typically has a rising F0 at the end of an utterance

Answer 47

Utterance-final rise of F0 is a cue to the listener, along with other cues (lexical, syntactic, situational), that a question is being asked F0 contours may also rise at the end of a declarative utterance when the speaker intends to continue talking (less than rise for questions) F0 contours may also be modified by the level of stress produced on a specific syllable

Answer 48

Nonverbal aspects of speech, usually related to prosodic variation, that convey emotion and physiological status. Can be thought of as a backdrop against which a message is transmitted.

Answer 49

In connected speech, an intensity contour varies over time primarily because consonants are less intense than vowels 7 to 14 dB intensity differences between vowels and consonants Intensity differences between consonants and vowels depend on many factors Type of vowel Consonant word position Syllable stress level Overall vocal effort level Sex of the speaker

Answer 50

English has multisyllabic words in which one syllable (sometimes two) is (are) stressed relative to the others. Lexically stressed syllables higher F0 greater intensity longer duration possibly a less reduced vowel formant pattern compared with unstressed syllables

Answer 51

Prominence--refers to syllables that “stand out” for a listener Often marked by intensity and duration, with F0 playing a weak role Clinical application Patients who have difficulty stressing syllables for lexical or sentence stress have multiple ways to make a syllable prominent

Answer 52

Patterning of segment or syllable durations across an utterance English is said to have a rhythm in which long and short-duration syllables alternate with each other. The long syllables are the stressed ones, the short syllables are unstressed. Usually a sequence of one long followed by several short syllables

Answer 53

English is considered a stress-timed language requires the duration between stressed syllables in an utterance to be nearly constant. In Spanish, duration between consecutive syllables, rather than stressed syllables, is nearly constant

Answer 54

Certain speech disorders exhibit rhythmic abnormalities English speakers with cerebellar disease may produce speech with a rhythm that distorts the normal approximation to stress timing by making all syllables roughly equal in duration. Pairwise Variability Index (PVI) acoustic measure of the relative duration difference between consecutive syllables in connected speech. Has potential as a diagnostic marker for different types of speech disorder

Answer 55

Acoustic phonetic analysis is useful for SLPs to gain insight into an individual’s speech production problems Concepts are relevant for AuD to understand the relevance to speech intelligibility and hearing devices

Answer 56

Acoustic characteristics of vowels, diphthongs, nasals, semivowels, fricatives, stops, and affricates are described with respect to formant frequencies, antiresonances, formant transitions, spectral shapes, segment durations, and segment intensities

Answer 57

F0 and intensity contours are significant prosodic characteristics Acoustic characteristics of lexical and sentence stress are variable across speakers