CSAD 222 Acoustic Phonetics and Diacritic Marks

for exam 3

how to describe a sound acoustically

sounds can be described acoustically based on time, frequency, and intensity

time

the duration of a sound; measured in milliseconds; can be measured in seconds; 1 second = 1000 milliseconds

frequency

the number of phonation cycles per second; measured in hertz (Hz) = cycles/second; perceived as “pitch”

relationship between frequency and pitch

as frequency increases, perception of pitch also increases; direct relationship

base pitch

the fundamental frequency (FO); 100 hz for males, 225 hz for females, 300 hz for children

intensity

amplitude of energy associated with a sound; measured in decibels (dB); perceived as “loudness”

relationship between loudness and intensity

as intensity increases, perception of loudness increases; direct relationship

waveform display

how speech is visualized; time is displayed on the x-axis and intensity is displayed on the y-axis

spectogram display

another way to visualize speech; time is displayed on the x-axis and frequency is displayed on the y-axis, then it is shaded based on intensity

formants

resonant frequencies of the vocal tract; unique for each vowel - how we can perceive different vowels; the first 3 are measured in english: f1, f2, and f3

F1 formant rules

inversely related to tongue height; the higher the tongue, the lower F1; the lower the tongue, the higher the F1

F2 formant rules

directly related to tongue advancement; the more fronted tongue placement, the higher F2; the more backed tongue placement, the lower F2

diphthongs

represented by two tongue positions and the glide between; not always a “clear” production of each

how consonants differ by manner and voicing

stops vs fricatives, orals vs nasals, voiced vs voiceless, obstruents vs sonorants

diacritic marks

provide further details; more thorough description than phonemes alone; marked with square brackets instead of virgules

steps of articulation of a stop consonant

1. obstruction of the airstream

2. increase in intraoral pressure

3. release burst

4. voiceless only: aspiration (burst of air)

   production of next vowel

stop gaps

a silent interval; reflects the time it takes for step 1 and 2 to occur; affected by voicing: MORE intraoral pressure required for voiceless

voice bar

vibration of vocal folds during stop gaps for voiced stops

voice onset time

(VOT) the time difference between step 3 (release burst) and and the onset of the next vowel and formants

difference between voiceless stops and voiced stops

voiceless have longer VOTs (25-100ms) than voiced (less than 20ms)

exceptions to VOT

can be 0 if release burst and voicing begin at the same time; can be negative if onset of voicing occurs before the release burst

unreleased stop

when step 3 of articulation of a stop consonant is missing

unaspirated stop

when step 4 of articulation of a stop consonant is missing when it should be present

aspirated stop

when step 4 of articulation of a stop consonant is added when it should be missing

fricative consonants

depicted as long bands of acoustic energy across a range of frequencies; the range of frequencies depends on place of articulation

sibilants

fricative consonants with increased intensity; perceived as being louder

non-sibilants

fricative consonants with low intensity; perceived as being quieter

people with high frequency hearing loss

those who have the most trouble hearing fricatives, especially non-sibilants

affricate consonants

includes acoustic information that is similar to both the stops and fricatives; has the same place of articulation and similar frequency range and intensity; voiceless have longer duration than voiced

sonorant consonants

produced with continuous voicing and a relatively open vocal tract; similar acoustically to vowels

nasal consonants

the oral cavity becomes a “sidebranch” of the vocal tract'; the place of articulation determines the size of the “sidebranch”

nasal murmur

acoustic energy radiating out of the nares

diacritic marks for voicing

indicate changes in manner of vocal fold vibration that are not expected; can be voicing or devoicing

dentalization

an unexpected change in place of articulation; when the teeth are involved and shouldn’t be

lateralization

an unexpected change in place of articulation; when airflow is directed towards the side of the mouth instead of flowing centrally through the mouth

nasalization

when a non-nasal sound is produced with nasality

nasal emission

when air escapes through the nares in production of an oral sound

denasality

when a nasal sound is produced without nasality