What are the parts of a (prevocalic) stop?
closure, release burst, formant transition
What is transition?
movement of articulators from one phoneme to another
What is a formant transition?
changing resonant frequencies of the vocal tract due to a movement of the articulators while voicing is occuring
What is aspiration
frication noise produced at the gottis
What is a transient?
(release burst) brief aperiodic sound with a rapid onset
What is a voice bar?
low intensity periodic noise produced when voicing occurs during the occluded portion of a stop
what is a silent gap?
period of closure without voicing
What are the two possibilities during an occlusion?
silent gap, voice bar
The spectra of a release depends mainly upon what?
the size of the cavity in front of the occlusion
List stops in order of highest to lowest frequency
alveolar, velar, bilabial
What is voice onset time?
the time between the release of the occlusion and the onset of voicing
What are the possibilities of VOT?
voicing starts before release (negative VOT)
voicing starts shortly after release (short lag)
voicing and release occur at the same time (zero VOT)
voicing occurs after the release (positive VOT or long lag)
What are the typical VOTs for voiced and unvoiced stops in english?
voiced: less than 20 ms
voiceless: greater than 25 ms
What is a click?
velar and other closure, air released
What is the source of noise in a fricative?
turbulent airflow
spectrum of fricative is determined by what?
size and shape of oral cavity in front of the constriction
Which fricatives are often classified as sibilants?
z, s, sh, zh
What makes a strident a strident?
produced with “sharper” constriction and tend to have more energy in their spectra
describe fricatives acoustically
aperiodic, high frequency energy
What are affricates?
stop followed by frication noise
How does affrication frication differ from regular frication?
shorter
What is carry-over coarticulation?
left to right, a preceeding sound changing an ensuing sound
what is anticipatory coarticulation?
right to left, an upcoming sound influences a preceeding sound
What is intonation?
changes in F0 across segments of speech
What is stress
varying frequency, intensity, and duration to make one segment more noticeable than another
F0 will ________ for a statement
fall
F0 will ______ for a question
rise
what are stressed syllables like in english?
higher F0
and/or duration
and/or amplitude
What is stressed used for in english?
sometimes, word meaning; highlight information at discourse level
What is phrase final lengthening?
last stressed syllable in a major syntactic phrase or clause is lengthened
Air moves from areas of _______ pressure to areas of ______ pressure
high; low
increase in volume carried out mainly by the ________ and _________
diaphragm and external intercostal muscles
speech breathing typically involves ______
more inspiratory effort, short period of inspiration
decrease in volume carried out by three main passive forces
elastic recoil of the lungs adn rib cage
torque or the untwisting of the cartilage connected to the sternum
what is myoelastic? (myoelastic aerodynamic theory of phonation)
elastic properties of the vocal folds
what is aerodynamic? (myoelastic aerodynamic theory of phonation)
onset of vibration via air pressure from lungs
What are the steps of the myoelastic aerodynamic theory of phonation?
- muscle activity adducts the vocal folds
- subglottal pressure builds up, eventually overcoming muscular force
- opening of the vocal folds from bottom to top
- air velocity increases through the constriction
- pressure on the vf decreases
- vf close from bottom to top
what is the longitudinal phase of the vf?
vf open back to front
vf close front to back
vibratory patterns of the vocal folds is…
periodic but not simple
what is the basic rate of vibration of the vocal folds called?
fundamental frequency
What is perturbation?
small changes superimposed on larger signals
What are the two types of perturbation?
frequency perturbation (jitter) amplitude perturbation (shimmer)
What is frequency perturbation?
timing variability between cycles of vocal fold vibration
What is amplitude perturbation?
amplitude variability between cycles of vocal fold vibration
What are some causes of perturbation?
difference in mass or tension of the left and right vocal fold
variations in lung pressure
mucous
articulators
What are the three regions of vocal register?
pulse register
modal register
falsetto
What is pulse register?
very low F0 associated with glottal fry
What is modal register?
normal conversational speech
What is falsetto
high F0
What type of vocal fold vibration is present for falsetto?
VFs elongated
vocal ligament tensed
lax cover
vibration mainly with just edges of glottis
often there is no midline closure leading to breathiness
What are the parameters of normal vocal quality?
maximum frequency range speaking F0 range of intensity at selected F0 values periodicity (measure by perturbation) noise
What is breathiness?
aspirated sound–
incomplete closure of vfs leads to air being continually released, more energy in high frequencies
What is roughness
raspy voice with low pitch–
common laryngeal disorder (laryngitis, irritated, swollen vfs, cancer
acoustically in low frquencies
what is hoarseness
combination of breathy and rough voice
The lower the HNR ratio, the…
more noise that exists in the voice
What is Harmonics to Noise ratio?
how much of voice is periodic vs aperiodic
What is a common method of determining the quality aspects of speech?
have people judge “naturalness”
what is SFF?
average F0 during conversational speech
F0 remains stable until about the sixth decade of life when:
males experience increase in F0 (thinning of vocal folds)
females experience decrease in F0 (hormonal changes)
What must clinical decisions about F0 take into account?
normal variation of F0, F0 sometimes influenced by factors other than vibration of vocal folds
What can F0 variability do?
reflect speakers emotional state
highlight emotion being conveyed
signal speaker’s intent
contrast different lexical items
what are three measures of F0 variability?
SD, range, semitones
amplitude level of speech highly dependent upon:
the environment
what is atypical level of conversational speech?
65-80 dB
reduced amplitude is consistent with which diseases?
parkinson’s, ALS, vocal fold paralysis
what is the SD of amplitude of “neutral” conversational speech?
10 dB SPL
Voice disorders that involve F0 (can use F0 as a measure for diagnosis?) are?
inappropriate use of F0, diplophonia, vocal nodules, vocal range problems
What is diplophonia?
produce two different pitches at the same time
What are some problems associated with segmentation?
how do you know when to segment out words in continuous speech?
there is no one-to-one correspondence between a phoneme and the way it is produced in continuous speech
how do adults segment?
lexical knowledge, acoustic cues, phonotactics, stress
what helps us differentiate between vowels, mainly?
formants, we think?
how do we tell vowels apart even though there is overlap?
vowel normalization - relations between formants (not absolute values of formants)
The ability to discriminate phonemes is closely related to what?
how phonemes are labeled
listeners do not seem to notice acoustic changes within a phonetic category BUT
are hypersensitive to the same acoustic changes across a phonetic boundary (aka there is a continuum but there is a point where we’re like.. THAT’S A P (as opposed to a b)
What are the cues for liquid perception?
rapid formant transition
What are the cues for glide perception?
short formant transitions
what are the cues for nasal perception?
formant structure and transitions
what are cues for stop perception?
formant transitions, burst frequency, VOT
what are the cues for fricative perception?
frication, spectral emphasis (for determining place), amplitude (sibilants from non-sibilants), transitions
What is the recognition point?
point at which a listener is capable of identifying a word from all other possible candidates