Acoustic Phonetics Test Flashcards

1
Q

What is a sine wave?

A

A curve / continuous representing periodic contractions and rarerafractions. Shows the maximum deviation of a particle from its position of rest. X-Axis: Time. Y-Axis: Amplitude. Are perceived as pure tones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a spectrograph/gram?

A

A spectrograph is a graph showing all three parameters of sound… X-Axis: Time. Y-Axis: Frequency and amplitude can be represented by the lightness/darkness/line intensity. Think LABBOOK They show the change of frequencies across time. Broadband spectrogram = best shows formants. Narrow band spectrogram= best shows harmonics.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a Spectrum?

A

A spectrum is a graph that shows the following two parameters of sound: X-Axis: Frequency. Y-Axis: Amplitude

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Periodic Waves

A

Occur at regular intervals. perceived as musical sounds as they appear to the human ear. Can be sustained for longer. Can be both simple or complex sine waves.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Aperiodic Waves

A

Have no distinct pattern. Contain different frequencies. These sounds do not appeal to the human ear and will be considered noise/unpleasant. They also fade away quicker.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Four processes of speech production:

A

airstream, phonation, oronasal modification (resonance) and articulatory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define the term “damping”

A

The reduction of amplitude due to the loss of energy. Very rapidly damped sounds are perceived as taps/clicks and known as transients.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Fundamental Frequency

A

Fundamental Frequency (in speech) is the lowest tone produced by the vibration o fthe vocal folds. The rate of the vibration of the vocal folds per second is the fundamental frequency otherwise known as F0.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does amplitude correspond to?

A

Loudness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Harmonics

A

The multiple frequencies that make up a complex periodic wave are individually known as harmonics. The harmonics of a sound are perceived as its timbre (quality) .

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does timbre correspond to?

A

Voice quality, attributed to harmonic structure. The greater the range of harmonics, the richer the quality of sound.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Components of voice quality

A

Harmonic structure, breathiness, jitter, shimmer.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Hoarseness corresponds with…

A

Raised levels of jitter and shimmer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Mass, length and tension of the vocal folds determines the…

A

frequency of vibration. This explains the difference between pitch in adults, males, females, children.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why do we describe pitch in terms of octaves/semitones?

A

Relates to human perception of hearing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Is the LX waveform a sound?

A

No. The LX waveform is the data measured by a laryngograph. It measures the adduction of the vocal folds. Each cycle of the vocal folds is known as a pitch period.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Average adult pitch period…

A

adult female (median F0 = 200Hz) the pitch period would be expected to be circa 5ms (0.005 s), for an adult male with a median F0 = 100Hz, the pitch period would be expected to be around 10ms (0.010 s)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is a CFx

A

The level of vocal fold irregularity perceived as creak. Represented as a cross-plot.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

In an LX (laryngograph) waveform, the peaks getting closer together corresponds to…

A

An increase in fundamental frequency thus pitch- vocal folds opening and closing faster meaning pitch periods ae getting shorter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Difference between first order DFx and second order Dfx

A

. First order DFx takes into consideration every single pitch period and corresponds the fundamental frequency. Second order DFx – outliers are removed by only accepting two adjacent values/ values on a smooth contour. Typically, second order DFx will be smaller. Comparing the two can give an indication of irregularity and creak in the voice.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Frequency range of young, healthy human ear.

A

20-20,000Hz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Resonance

A

Phenomenon whereby acoustic system amplifies sound waves whose frequency matches one of its own natural frequencies of vibration. i.e. resonance occurs when on one or more of the frequencies in the sound source match the natural frequency of a cavity. In speech, there is more than one natural frequency in the vocal tract therefore speech sounds have more than one resonant value (known as formants) e.g. child’s swing- push will be amplified when push energy matches natural frequency of the swing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Laryngeal sounds

A

harmonics (resonant values) created by vibration of the vocal folds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Fricatives are aperiodic sounds, true or false?

A

True. Aeriodic sounds are produced by narrow constriction in the vocal tract. On the spectrogram, this would be represented by high frequency acoustic energy which is dark and intense, and therefore has high amplitude. This is typical of many voiceless fricatives, such as [f] and [s] in the English sound system.

25
Q

Source-filter theory of speech production is…

A

the process of the generation of aa sound source, with its own acoustic properties, which is then filtered and shaped in thevocal tract

26
Q

Vowel sounds are characterised by their….

A

formants.
F1 relates to function of the tongue. F2 is characterised by constrictions at the front or back of the vocal tract. With this in mind, vowel patterns can be ascertained

27
Q

Formants are lower in longer tracts, true or false

A

True. Male vocal tracts are generally longer than females. Adults vocal tracts are longer than children’s. Formant values can be lowered by lip-rounding, which also lengthens the vocal tract.

28
Q

Frequency in speech context…

A

relates to the number of times the vocal folds open and close per second.

29
Q

What is vocal fold oedema?

A

swelling / irritation of the vocal folds

30
Q

What is Fourier’s basic principle?

A

ALL complex periodic waveforms can be analysed into a sum of harmonics.

31
Q

Sound is associated with

A

pressure variations in a medium

32
Q

The amplitude of a wave is

A

best described as the maximum displacement from rest of the particles in the medium.

33
Q

The sound of a damped tuning fork oscillation

A

maintains a constant frequency.

34
Q

Pitch extracted from a stream of speech may be discontinuous because…

A

the voiceless elements in speech have no associated ‘pitch’

35
Q

Fundamental frequency is lower with

A

smaller inter-harmonic intervals and vice versa

36
Q

vocal fold vibration is determined by

A

mass, length and tension of the vocal folds

37
Q

vocal fold vibration occurs via

A

the Bernoulli principle combined with neuromuscular activity

38
Q

Two preconditions for a sound wave

A
  1. a vibrating source 2. a medium
39
Q

True or false? A sine wave graph is the closest graph that relates to human auditory perception

A

False, a sine wave graph will give us a representation which is closer to our visual perception of a sound wave, with x-axis: Time and y-axis: amplitude. The closest auditory representation would be a Spectrum, auditory perception is dependent on the frequencies and their respective amplitudes which are the constituent frequencies in a complex wave,

40
Q

Average pitch ranges for men, women and children.

A

Men: 100Hz, Women: 200Hz, Children: 300Hz

41
Q

The glottal tone (aka the voice coming out of the larynx) contains only a single frequency, true or false?

A

FALSE, the fundamental frequency is accompanied by a number of harmonics which are whole number multiples of the fundamental frequency. Thus, the glottal tone is a complex wave sent out in pulses by the vibrating vocal cords.

42
Q

Define the difference between a simple and a complex wave?

A

A simple or sine wave represents the pattern of disturbance caused by the movement of energy travelling through a medium and vibrating at a single frequency, also known as pure tone.

The amalgamation of sine waves vibrating at different frequencies would be known as a complex wave, therefore a complex wave will always have more than one frequency. A complex periodic wave may be expected to be perceived as having a pitch .

43
Q

Harmonics are multiples of the fundamental frequency, true or false?

A

True. The second harmonic is the fundamental frequency x2, the third is F0 x3, and the fourth is F0 x4, and every subsequent harmonic is the next whole number multiple

44
Q

Higher frequencies are produced with lower amplitude, true or false?

A

True. There is a certain amount of energy consumed with every frequency with higher frequencies being produced with less energy.

45
Q

Why do nasals contain an extra formant on a spectrogram ?

A

Because of the additional resonance chamber i.e. the nasal cavity

46
Q

Resonant values that amplify preferred frequencies within the vocal tract/ the preferred resonant frequencies of the vocal tract. You can change these by changing the size and shape of the vocal tract.

A

Formants

47
Q

Fx (fundamental frequency trace)

A

When they take the fundamental frequency from every pitch period (e.g. taken from lx trace) and plot it against a graph that has time and frequency

48
Q

Lx trace

A

Represents vocal fold vibration (opening via subglottal pressure and closing via Bernoulli effect of the glottis). Each pitch period represents the fundamental frequency (as it represents closure per second). Allows you to see periodicity, e.g peaks getting closer together, corresponding to an increasing fundamental frequency.

49
Q

Amplitude is measured in

A

Decibels (Db)

50
Q

Frequency Bandwidth

A

the range of frequencies being considered

51
Q

Transients

A

are sounds that are damped quickly

52
Q

Formula for frequency

A

F = 1/T

53
Q

How can nasals be identified on a spectrogram?

A

By means of their low frequency (0-100Hz) ‘nasal murmur’ and a gap higher up on the frequency axis described as anti-resonance as these frequencies are soaked up by the nasal cavity

54
Q

Voice Onset Time (V0T)

A

Interval between the burst of a plosive and the onset of the following vowel. A brief VOT (<30ms) is associated with voice plosives. A longer VOT (>31-140ms) is associated with voiceless plosives.

55
Q

True or false… whisper can be attributed to turbulent air (forced through the glottis) and generating aperiodic noise, being modified.

A

True

56
Q

Whisper has no perceived pitch, true or false?

A

True. Whisper has no perceived pitch and cannot carry intonation or tones, because it is aperiodic.

57
Q

true or false… consonants carry the energy of speech?

A

FALSE. vowels carry the energy of speech, consonants determine intelligibility

58
Q

Which fricative assumes the resonance of adjoining sounds

A

Voiceless glottal [h]