exam 2 study guide Flashcards
Frequency
-number of times vibration occurs per second
-Hz or cps
Intensity
-degree or amplitude of particle displacement
-dB
Time
-time in which a cycle is complete
-seconds
Wavelength
-distance a wave travels in one cycle
Vocal Fundamental Frequency
-rate of vibration of vocal folds/ rate that they open and close
Wave composition of periodic sounds
-vibration occurs at a set rate and repeats
Wave composition of aperiodic sounds
-vibration does not have a repeated pattern; sound is a result of forcing air through constriction
Frequency characteristics of aperiodic sounds are affected by
Frequency is determined by:
-size and shape of opening
-texture of articulatory surfaces
-place of obstruction
Resonance
selective amplification and dampening of frequencies
results from reflection and concentration of sound waves in a cavity
Natural Resonating Frequency
frequencies close to NRF are amplified and those far away are damped
Harmonic analysis
complex periodic sound waves can be broken into sinusoids or simple sound waves (pure tone)
overall energy is not changed, just redistributed over different frequencies
Measurement of acoustic parameters
frequency
musical scale
made of octave, tones, and semitones
Orchestral standard scale
A4= 440
C0=16.35 Hz
Octave, Tones, Semitones
Octave is broken down into 6 tones
Tone is broken down into 12 semitones
Logarithmic scale with base of 2
ratio of one octave to the next is always two
100-200
500-1000
Formula of Number of Octaves
N(O)
N(O)=3.32*Log 10 of F1/F2
Formula for Number of tones
N(t)
N(t)=6octaves
N(t)=19.92Log 10 of F1/F2
Formula for number of semitones
N(st)
N(st)=12octaves
N(st)=39.84Log10 of F1/F2
Formula for Frequency Level of Octaves
FL(O)
FL(O)=3.32*Log10 of F/16.35
Formula for Frequency Level of Tones
FL(t)=19.92*Log10 of F/16.35
Formula for Frequency Level of Semitones
FL(st)=39.84*Log10 of F/16.35
Measurement of acoustic parameters- intensity
standard scale: Sound Pressure Level
.0002 dynes/cm^2 because it is the lowest that humans can hear
Bel
original unit of measurement
had logarithmic scale with base of 10 (1 Bel = a sound 10x greater)
Decibel
1/10th of a Bel
provides a definite scale
Formula for Numbers of Bels using Power
N(Bel)= Log10 of P1/P2
Formula for Number of Bels using Pressure
N(Bel)= 2Log10 of Pr1/Pr2
Formula for Number of Decibels
N(dB)=20*Log10 of Pr1/Pr2
Formula for Sound Pressure Level
SPL(dB)=20*Log10 of Pr/.0002 dynes/cm^2
power
amount of work completed
measure of electrical power
Pressure
rate at which work is completed
replaced power because instruments began to use pressure
2 is constant because pressure is proportionate to the square root of power
Intonation
prosody or suprasegmental aspects of language
sentence types, and emotion, physical/mental state, and personal characteristics can be conveyed
Habitual pitch
fundamental frequency used most of the time
determined by narrowing range and prolonging vowel
Natural pitch
fundamental frequency most efficient for speaker
from 1/3 or 1/4 the bottom of the pitch range with falsetto (1/3 without falsetto)
Optimal pitch
fundamental frequency best for the individual
ideally same as natural pitch
Falsetto pitch
one octave above the habitual pitch
created by holding cartilaginous portion of the vocal folds tightly together, reducing vibrating length by approximately one half
Vocal tract characteristics
-air filled tube closed on one end
-sequence of container that act as filters by passing the frequencies that fall within their bandwidth and deamplifying those out of their frequency
-tract is a variable resonator whose frequency response changes depending on shape
Quarter wave resonator
vocal tract
air filled tube that is closed on one end
VFF range of infants
500 Hz to 2000 Hz
VfF range of 7-8 year olds
280-300 Hz
same for males and females
VFF for adult and elderly men
120-140 Hz
elderly-140 Hz
VFF of adult and elderly women
200-300 Hz
elderly- 200 Hz
Jitter
vocal harshness
(Variation if VFF)
Shimmer
variation in vocal amplitude
How to find wavelength
Multiply length of vocal tract by 4
Harmonics
sections of vocal tract pass frequencies that fall in their range and amplify those out of the range
resonant frequencies are odd number multiples of the lowest resonating frequency
Formula with harmonics
F=speed of sound/wavelength
speed of sound- 34,000 cm^2
Sound source filter theory
formalized manner in which vocal tracts filters glottal sound
describes by sound travels out of the mouth and into environment
radiation characteristic
effect of the mouth acting as a high pass filter when coupled to the environment
effect of sound traveling out of vocal tract and into environment
3 elements involved in production of speech are represented by spectrums
- source function
- transfer function
- output function
source function
glottal spectrum
shows sound as it exists at the level of the glottis before it is modified by vocal tract
F(0)- greatest amplitude with higher harmonics being damped at rate of 12 dB per octave
acoustic energy represented by to 5000 Hz
transfer function
does not represent sound but indicates resonance curve which demonstrates the male vocal tract producing schwa with resonance frequencies at 500 Hz, 1500Hz, and 2500 Hz
output function
demonstrates sound as it leaves the lips
glottal sound after it has been filtered by vocal tract
same F(0) and harmonics as glottal sound, but some have been amplified and others attenuated
What makes up a vowel
VFF (F0) and Harmonics (F1, F2, F3)
corners of the vowel quad
/i/ /æ/ /u/ /a/
3 Resonating cavities
- pharyngeal cavity: vocal cords do not shape
- nasal cavity: does not move and cannot change shape
- oral cavity: can change vocal tract (lips, jaw, and tongue)
Formants
regions of high energy and frequency
F1 corresponds to
tongue height
F1 increases as tongue height decreases
F2 corresponds to
tongue advancement
anterior v posterior
more anterior= F2 increases
Dipthongs
movement from one position to another
/ɑɪ/
/ɑU/
/ɔɪ/
/ju/
Where are formants created
F1- vocal folds
F2-lips
F3-tongue retroflexed
Two types of consonants
voiced consonants
voiceless consonants
voiced consonants
sounds produced by vocal folds
periodic component
voiceless consonants
sounds produced by forcing air through constriction or point of articulation
aperiodic component
consonants with both voiced and voiceless characteristics
quasiperiodic- most voiced consonants are
acoustics of the manner of production
acoustics of consonants are affected by manner of production and change as manner changes
Types of consonants
plosives
fricatives
affricates
nasals
glides
axis of the spectrogram
time
frequency
darkness of the spectrogram
high amplitide
Vowels
3 formants are important
mostly first two -
1- VFF or F(0)
Glides
semi vowel and sonorants; very quick
vowel-like but short in duration
defined by transitional elements
y, w,
all periodic
Liquids
very quick
l, r
semi vowels produced with relatively prominent sonority and with some degree of lateral emission of air
Four features of stops
-“silent gap” that occurs when there is no flow of air out of vocal tract
-noise burst at moment of release
-speech with which acoustic signal attains max intensity
-change in the first formant frequency that occurs as the vocal tract changes shape after release of initial syllable
plosives
sudden onset and short duration; followed by aspiration
aperiodic or quasi-periodic
p, b, t, k, d, g,
How fricatives are produced?
gradual onset and longer duration
V-Q
VS-A
f, s, z, v, th
How affricates are produced?
sound onset followed by sound produced at point of constriction
aperiodic or quasi-periodic
ch , j
Nasal formant/murmur
produced with open velopharyngeal system port
Antiresonants
filter effect of the vocal tract characterized by loss of acoustic energy in particular frequency region
occurs with nasal sounds becuase they are relatively weak
murmur
acoustic result of adding nasal branches to vocal tract (larger, longer resonator=lower frequency)
200-300 Hz range in males
Why do nasals have little intensity?
due to low frequency resonance due to the larger total resonating cavity
(adding nasal cavity to vocal tract by lowering velum)
