77 terms

Speech and Hearing Exam #2

3 contrasts used to classify or analyze sound
1. simple/complex
2. periodic/aperiodic
3. transient/continuous
Sounds that appear in the real world
complex sounds
graphic representation of the time domain
waveform (a/t)
graphic representation of frequency domain
amplitude spectra
graphic representation that allows for a display of all 3 sounds
speech spectrogram
waveform axes and units of measurement
spectrogram axes and units of measurement
freq/time (w/ darkness representing the amp.)
frequency domain (spectrum) axes and units of measurement
mathematical analysis performed on complex sound to identify its frequency or spectral components
Fourier analysis
F0 definition
= fundamental frequency in periodic complex sound, also it's the 1st harmonic
harmonic definition
frequency components of periodic complex sound
how can we predict the harmonics above F0
multiply the number of the harmonic by the F0
what can we predict regarding the amplitude of harmonics above F0
amplitude decreases in intensity as harmonics increase in frequency
octave definition
twice or 1/2 of any frequency
resonant frequency definition
a particular frequency that passes best through an object - sets an object into vibration
*more mass = lower resonant freq.
*more stiffness = higher resonant freq.
*longer = lower resonant freq.
4 major types of acoustic filters
1. low pass
2. high pass
3. band reject
4. band pass
low pass filter definition
passes through frequencies and diminishes below the cut-off frequency
high pass filter definition
passes frequencies above cut-off frequency
band reject definition
rejects frequencies between 2 cut-off frequencies
band pass definition
filters freq. above a cut-off freq and below a cut-off freq
cut-off frequency definition
the freq values above, below or between which the filter passes the sinusoidal components w/o reducing their amplitudes *essentially, where attentuation begins
systems of speech production
1. respiratory system
2. laryngeal system
3. supralaryngeal system
respiratory system definition
power source (lungs)
laryngeal system definition
creates sound (vocal folds and glottis)
supralaryngeal system definition
shapes sound (articulators and resonators)
jaw, tongue, lips, velum (velopharyngeal port) - all direct sound into the resonating cavities and change their shape are size
pharyngeal cavity, oral cavity, chest cavity and nasal cavity - all shape the spectrum of the glottal source
complex periodic sounds
vowels, diphthongs, nasals, glides, liquids, voiced fricatives, voiced plosives and voiced affricates
complex aperiodic: noise
voiceless fricatives, voiceless affricates, voiced fricatives, voiced affricates
3 contributions to the acoustic speech product
1. glottal source
2. transfer function
3. radiated sound wave
glottal source definition
glottis and vocal folds
transfer function definition
filtering of the glottal source as a result of the vocal tract resonances
radiated sound wave
occurs at the lips
corresponding locations in the vocal tract
glottis, oral/nasal cavity and lips
12 dB/octave definition
rate at which harmonics decrease in amplitude from glottis
harmonics definition
a component frequency of a complex wave that is an integral multiple of the fundamental frequency
effect of tube length on resonance
longer tube = lower resonant frequency
formant definition
vocal tract resonances corresponding to peaks in the transfer function and radiated output spectrum (F1, F2, F3) - *a group of enhanced harmonics
F1 associated articulatory movements
mouth opening, jaw lowering or tongue lowering
F2 associated articulatory movements
location of tongue hump
F3 associated articulatory movements
location of tongue placement
F1 vowel class
high vowels have lower F1 and low vowels have higher F1
F2 vowel class
tongue to front have high F2 and vowels w/ tongue toward back have low F2
F3 vowel class
vowel place
diphthong definition
vowels that change in location and degree of constriction over the course of production - *2 vowels together that move rapidly from one to the other
nasal murmur definition
the addition of a resonance below 500 Hz
effect of anti-resonances on the amp of nasals
it decreases the amp of higher frequencies
resonant areas for nasal consonants
all non-nasal areas + nasal cavity and velopharyngeal port
how does F3 participate in consonant differentiation?
placement of tongue tip (fine tongue tip movement differences)
4 phases of articulation of stop/plosive
1. closing
2. hold
3. release
4. vowel
primary acoustic features on a stop/plosive
noise spike that occurs (on spectrogram) when sound "explodes" in sound production
roll-off definition
rate of attenuation
tube resonance relation to fundamental freq
the longer the tube (lip rounding) lowers the formants because tube is lengthened
SEMIVOWEL manner of articulation
NASAL manner of articulation
STOP manner of articulation
AFFRICATE manner of articulation
FRICATIVE manner of articulation
VOT (voice onset time)
duration (or time) between plosion/noise spike & onset of the vowel *is longer for voiceless plosives than for voiced plosives
simple sound definition
sound that is comprised of only one frequency (SHM, pure tone, sinusoid)
complex sound definition
sound that is comprised of more than one frequency
periodic sound criteria
-the freq content is specific
-the waveform repeats itself
-may be simple or complex
aperiodic sound criteria
-freq content may be random
-randomly distributed frequencies may appear within a specified range
-the waveform does not repeat
-always complex
-noise/white noise
transient noise criteria
-the signal has a beginning and an end
-acoustic results of suddenly stopping and starting are a splattering of the signal across a broad range of frequencies
-working definition - very brief acoustic signals
*usually a sound that is short in duration and when it stops there is a splattering of frequencies (ex: clap, /k/, /p/, /t/
continuous sound criteria
-definitions - the signal has no beginning or and end - the signal has "ramped" or shaped beginning and end points to avoid transient effects
-may be simple or complex
*starts and stops but not very fast; ramps up (ex: "sh" and "ah")
a resonator that modifies the freq of vibration
complex aperiodic: transient
voiceless plosives, voiceless affricates, voiced plosives, voiced affricates
vowels (acoustic features)
complex periodic sound
diphthongs (acoustic features)
complex periodic sound
nasals - m, n, ng (acoustic features)
complex periodic sound
glides/liquids - w, r, l, j (acoustic features)
complex periodic sound
voiceless fricatives - f, s, th, sh, h (acoustic features)
complex aperiodic: noise
voiceless plosives - p, t, k, (acoustic features)
complex aperiodic: transient
voiceless affricate - ch, (acoustic features)
complex aperiodic: noise and complex aperiodic: transient
voiced fricatives - v, th, zh (acoustic features)
complex periodic, complex aperiodic: noise
voiced plosives - b, g, d (acoustic features)
complex periodic (briefly), complex aperiodic: transient
voiced affricates - juh
complex periodic (briefly), complex aperiodic: noise and complex aperiodic: transient