Midterm Flashcards
Experimental Phonetics
Any investigation of speech by means of instruments that can be used
- to visualize the speech event
- to provide a basis for measurement
The Speech Chain
Linguistic level, physiological level, acoustic level, physiological level, linguistic level
Acoustic Level
The only stage in the speech chain where speech exists outside of the human body, defines the common ground between speech production and perception
Sound
Transmission of a pattern of motion through a medium in a longitudinal wave form, most commonly the medium is air
Air Movement
Air always moves from an area of high pressure to an area of lower pressure
Sound Wave
Variations in air pressure, alternating pattern of compressions and rarefactions
Longitudinal Wave
The motion of particles is in the same direction as the direction of the wave
Transverse Wave
The motion of particles is at a right angle to the direction of the wave
Waveform
A visual representation of sound showing changes in air pressure over time at a specific point in space, single entity
Simple Waveform
Has the form of a sine curve
Sine Curve
Presents a mathematical representation of circular motion, simple periodic wave
Pure Tone
A sound that creates a single sine wave, ex. a tuning fork
Period
The duration of a single cycle, measured in milliseconds
Frequency
The number of cycles per second, measured in hertz
F = 1 divided by Period(s)
F = 1000 divided by Period(ms)
Amplitude
Peak-to-peak height on the waveform or maximum distance from the baseline, measures the amount of pressure change in pascals
Amplitude and Loudness
Higher amplitude –> louder sound
Intensity and Loudness
Doubled intensity –> doubled loudness
Intensity
The amount of kinetic energy (= the force that causes the movement) received from the sound wave, measured in decibels
Amplitude and Intensity
Doubled amplitude –> quadrupled intensity
Periodic Waves
Waveforms with a repeating pattern, cyclic
Simple Periodic Waves
A single sine wave, no sound produced in language
Complex Periodic Waves
All periodic waves but simple sine waves, vowels, voiced fricatives, nasals, liquids, glides, and sonorants
Aperiodic Waves
Waveforms with no repeating patterns, “noisy” sounds, voiceless fricatives
Transient Waves
Waveforms with a very short duration, voiced and voiceless stops
Voicing and Periodicity
Each period of the acoustic signal corresponds to a single cycle of vocal fold vibration
Fourier Analysis
Identifying the sine wave components in a complex waveform
Spectrogram
Visualizes the sine components of a complex waveform
Spectrum
Two-dimensional diagram that shows the frequency and amplitude (or intensity) of each sine wave component in the given sound
Spectra of Actual Vowels
Consists of an infinite series of vertical lines, equally spaced with distinct peaks
Acoustic Resonator
An object that is set into vibration by an external force changing the quality and making the sound louder, in this case vocal tract
Sound Source
Vibrating vocal folds, series of sine waves equally spaced out
Source-Filter Theory
Combination of the spectrum of the source and the frequency response curve of the filter
Harmonics
The x-value of each vertical line (= the frequency of each sine wave component), each harmonic is a multiple of the first, lowest harmonic, determines pitch by the vocal folds
Fundamental Frequency
The first, lowest harmonic, is the pitch of the sound, the frequency of the vocal fold vibration
Vocal Tract
Resonates the source sound by allowing certain frequencies to pass through with greater amplitude
Frequency Response Curve
Indicates how much amplitude/intensity will be added or taken away from each possible input frequency during filtering
Formants
The x-value of each peak in the frequency response curve, determines the sound quality by the vocal tract
Source Spectrum
Each vertical line represents the frequency of each sine wave component and its amplitude
Resonant Frequency Equation
F = (speed of sound in the air)/(length of the vocal tract * 4)
Lip Rounding
Changes the shape and lengthens the vocal tract, decreases formants F2 and F3
Velum Position
Lowering the velum allows for air to pass through the nose, adding another “tube” filter to the system and adds an additional formant
Speech Production
Involves the vibrating of vocal folds and the filtering of that sound through the vocal tract
Lowered Tongue
Increases the oral cavity, increasing F1
Fronted Tongue
Increases the pharyngeal cavity, increasing F2
Natural Frequency
When an object is set into vibration, the rate at which the object vibrates
Resonance
A large increase in the amplitude of a vibration when an external force is applied at the natural frequency of the object
Lower Tongue
Higher F1
Raised Tongue
Lower F1
Spectrogram
A graphic representation of the energy of the frequency components of the speech as a function of time, time as x-axis, frequency as y-axis, energy (amplitude) as color scale
Spectrograph
Device to produce spectrograms
Spectrography
Technic to produce spectrograms
Spectrogram Vertical Bars
Each striation corresponds to a single cycle of vocal folds vibration
Spectrogram Horizontal bars
Correspond to the formants of a vowel
Vertical Bar Spacing in Spectrum
If the fundamental frequency increases, the spacing between vertical lines (= harmonics) increases
Vertical Bar Spacing Spectrogram
If the fundamental frequency increases, the spacing between vertical lines (= size of the gaps between individual striations) decreases.
Shading
Indicates softness, if very light the sound is soft
Vowels
Carry greater energy than consonants (vertically wider on waveform and darker on spectrogram) and have formant structures, contain more information within articulation, classified based on frequency
Consonants
Contain more information before or after articulation, relevant information is shown in the transition from/to other sounds, classified based on frequency, intensity, and timing
Vocal Fold Vibration
Air pressure generated by lungs, air is then converted into a series of puffs, each puff creating an alternating compression and rarefaction of air, producing a periodic complex wave
Turbulence Generation
Air pressure is generated by lungs, air goes through open glottis, air flows through narrow constriction making it turbulent, producing a continuous aperiodic wave
Sudden Pressure Change
Air generated by lungs, air goes through open glottis, air meets complete constriction causing change in pressure, producing a transient wave
Constriction Interval
The time corresponding to the constriction in which production of a consonant occurs between two articulators at some place in the vocal tract
Formant Transition
When a vowel precedes or follows the articulators moving into their target position
Stops (Plosives)
A complete constriction of the vocal tract then airflow resuming in a burst of sound, most common consonant
Acoustic Cues of Stops
Stop gap (complete closure with silence), burst noise (sudden noise/darkness), voice onset time, formant transition
Fricatives
Narrow constriction produced when two articulators come close to each other, airflow becomes turbulent going through narrow passage
Venturi Effect
Flowing material becomes faster when it goes through a narrow area
Affricate
A sequence of stop followed by fricative at the same place of articulation
Obstruents
The only consonants that have a phonemic voicing distinction in English, consists of stops, fricatives, and affricates
Nasals
The place and manner of articulation takes place in the mouth, but the soft palate is lowered and the air flows through the nose, low-frequency formants
Liquids and Glides (Approximants)
A constriction in the oral cavity, narrowing the vocal tract but not enough to create turbulence, airflow through the oral cavity is smooth, division of airflow
Sonorants
