Lecture 2 Branches of Phonetics, Methods and Techniques

Lecture 2: The Three Branches of Phonetics. Methods and Techniques. 

1. Articulatory Phonetics

Studies the articulatory properties of speech sounds – how they are produced.

Methods: Instrumental vs. non-instrumental. Non-instrumental: one’s own feeling of the

position of the speech organs – KINAESTHETIC feeling (PROPRIOCEPTION).

Drawback: inaccurate and limited.

INSTRUMENTAL TECHNIQUES

PALATOGRAPHY – powdering the palate and observing the trace left after the contact.

Advantages: more accurate. Limits: applicable only for certain sounds

and very short utterances.

X-ray photography: still or moving. Advantages: very accurate, but… Disadvantage: imposes health risk. Today replaced by Magnetic Resonance Imaging

(MR), which is not health hazardous. Electromyography: measures muscular movement

during articulation by means of an electrode pressed against the throat.

Electro-aerometer: Device for measuring the force of the airstream coming out of the oral cavity

ACOUSTIC PHONETICS

Examines the acoustic properties of sounds by studying the physical features of variation in air pressure produced by vocal tract movements.

A speech sound has the characteristics like any other wave.

Characteristics of the speech sound wave:

1. Frequency – number of oscillations per second, measured in Hertz (Hz).

With a higher number of oscillations, we perceive the sound of a higher pitch (musical tone).

2. Amplitude – the distance between the point of rest and the highest/lowest points it reaches.

A sound with a higher amplitude is perceived as a louder sound. Measured in decibels.

3. Duration – the length of a sound, measured in seconds.

A simple wave form

Methods and techniques of acoustic phonetics

Oscilloscopy: the waveform displayed on a screen.

The oscillogram of the vowel /a/.

Time (s)0 0.0881633

-0.495

0.5803

0

2. Sound spectrography/spectrogram is the technique in which all relevant frequencies of a speech sound are seen.

Vowels are seen as black horizontal stripes patterned on the screen. These are FORMANTS, or concentrations of energy.

Spectrogram of the word peck

Spectrogram and oscillogram of the word sky

AUDITORY PHONETICS

The branch which studies how speech sounds are perceived.

For ethical reasons, the only methods used here are indirect – through listening and response tasks.

The devices used are cassette/CD players and computers.