Table of Contents
4.1 Measuring Duration Top
Once the sound file is open in the Editor window, you can read the total duration easily from the duration bar, but if you want to know the duration of your selected part, you can follow the following steps (Styler, 2012:13)
1. Select the portion of the file you’d like to measure with the cursor
2. Read the duration of the selection (in seconds) from the duration bar along the bottom of the Editor window
3. Editor à Query à Get selection length and read your selection in the "Info" window
If you’d like to know the duration of an entire file, just select the file in the Objects window and select
Objectsà Queryà Query Time Domainà Get Total Duration
"Voice Onset Time" (VOT) is the time between when the stop is released and when the voicing of the following vowel begins. Measuring this time, which can be positive (say, for the English voiceless aspirated stop [tH]), around zero (for the English "voiced" stop /d/, or, more commonly, the voiceless unaspirated [t]), or negative (for fully voiced stops, where voicing starts before the stop is released, as found in most non-English languages). Languages classify their stops largely based on voice onset time, and it’s an excellent way of proving the "voiced/voiceless" phonological distinction.
Measuring voice onset time (VOT) is very easy to do in Praat, as it’s just a duration measurement between two set points, the release of the stop and the start of voicing.
1. Find the stop release
2. Find the start of voicing
3. Select the span between these two points
4. Read the duration of the selection (in seconds) from the duration bar along the bottom of the Editor window
If the start of voicing came before the stop release, the VOT is negative. Otherwise, the VOT is positive. In general, voiced sounds (in languages other than English) will have a VOT which is negative. Voiceless unaspirated sounds will have a VOT which is around 0, and aspirated sounds will have a positive VOT. (Styler, 2012:14)
4.1.2 Linking duration Top
As Heike (1987) observed, linking can occur in English between two consonants, between a consonant and a vowel, or between two vowels.
We can decide whether there is linking by measuring the duration of CC, CV, and VV in Praat.
Pause is defined as “any interval of the oscillographic trace where the amplitude is indistinguishable from that of the background noise” (Duez, 1982, p.13). Intensity can be considered the acoustic cue to measure pause (Chen, 2005). Pauses could be analyzed by measuring pause duration, pause distribution, and pause location. As a common practice, only those pauses greater than 100 ms, the cut-off for pauses (Griffths, 1991), were considered to be a “pause”. Therefore, we can decide whether there is a pause by measuring the duration between two adjacent words.
Speech rate is defined as the total duration of a sentence (including pauses). The most common measurements of speech rate are syllable per second (sps) and words per minute (wpm) (Buck, 2001). The total duration and SPS were calculated. Since measurement of syllable duration is the major focus in this dissertation and the selected speech samples from the four groups were short and identical, the measurement of WPM was not employed here.
In this chapter, we will discuss the application of Praat in the analysis of the word stress and intonation. Both of stress and intonation belong to the suprasegmental features. There are two kinds of stress: word stress and sentence stress. Word stress is concerned with the stressing of individual words of two or more syllables when they are pronounced in isolation. By intonation we mean the rise and fall of the pitch-change of the voice which take place on the nucleus.
In English we usually find that simple words consisting of two or more syllables have a strong stress on one of these syllables and a weak stress on the remaining syllable or syllables. Stress plays an important role in communication, for it distinguishes different meanings when the stress is put in different positions.
“All stressed syllables in words have one characteristic in common, and that is prominence.
Prominence is produced by four main factor: (i) loudness(intensity), (ii) length, (iii) pitch(Fundimental Frequency/F0), (iv)quality. Generally these four factors work together in combination, but experimental work has shown that these factors are not equally important; the strongest effect is produced by pitch, and length is also a powerful factor. Loudness and quality have much less effect.” (Roach 2009:74)
Since stress is manifested as rise in pitch, greater intensity (loudness) or greater vowel length, the analysis of stress must include various elements of acoustic analysis, like waveform, spectrogram, and pitch contour.(See Figure 4. 1 )
Figure 4.1 The waveform, spectrogram, and pitch contour of sound
(retrieved from Stonham’s handout: p3, http://stonham.dyndns.org/phonetics/handouts/prosod_hndt.pdf)
Since stress is manifested as rise in pitch, greater intensity (loudness) or greater vowel length, the analysis of stress must include various elements of acoustic analysis, like waveform, spectrogram, and pitch contour. You can follow the following standard procedure in Praat to analyze the stress.
1. Open the sound file in Praat ( Open→read from files…)
2. Select the file and click "View and Edit” on the right side
3. In the Edit window, select Spectrum→Show spectrogram (the default setting is showing the spectrogram)
and then select Pitch→Show pitch, and you will see the following window Figure 4.2: the pitch analysis is laid over on the spectrogram, but when you export them to the Praat objects list they will be treated as separate objects
4. To export different windows, you can go to Spectrum and then choose Extract visible spectrogram, then a new file will appear in your Praat objects list as 'Spectrogram untitled' in Figure 4.3
5. Then go to Pitch and choose Extract visible pitch contour, and then a new file will appear in your Praat objects list as 'Pitch untitled'as shown in Figure 4. 4
6. You can also draw the graphics of the waveform by selecting Fileà draw visible sound
7. You can also draw the graphics of pitch track by selecting Pitchà draw visible pitch contour
8. You can also draw the graphics of the spectrogram by selecting Spectrogram à paint visible spectrogram
Please see the output in Figure 4.5, which shows waveform, pitch track, and spectrogram
Figure 4. 5
See details of drawing and painting in Praat in 1.3.4
Let’s look at two examples of analysis of lexical stress in Praat:
Example 1 Figure 4.6 Record /rI Ûk??ùd/
Figure 4.7 Pitch contour of reCORD
Figure 4. 8 Record / Ûrek«d/
Figure 4.9 Pitch contour of REcord
The word ‘record’ is divided into two parts –‘re-’ and ‘-cord’.
1. In the first one, re’cord, the stress is put on the second syllable.
(1). In “re-”, the pitch is falling down, while in “-cord”, the pitch is rising, especially in the part of vowel.
(2) The stressed syllable is higher than unstressed one. And the duration of the second syllable “-cord” is longer than the first.
2. In the second one, the stress is put on the first syllable.
(1). It is obvious that the duration of the first syllable “re-” is much longer than the one in the first example. And the pitch is rising in the first syllable.
(2). in the second syllable, the duration is shorter and the pitch is falling down.
The table below shows this more clearly;
Let's look at another two examples:
Figure 4.10 Contrast /kɒn'trAùst/
Figure 4. 11 Pitch contour of ConTRAST
Figure 4.12 Contrast /'kɒn trAùst/
Figure 4. 13 Pitch contour of CONtrast
Intonation is determined by many elements like pitch, energy, duration, tempo and sound quality. Pitch plays a more important role than the remaining elements. As English is an intonational language, the intonation expresses speakers’ emotion and attitude. Native speakers use different intonations in different sentence types.
In Praat, we mainly use pitch contour to indicate different tones, like falling and rising tones.
1. Select the sound in object list
2. Click View&Edit
3. Pitchàtick show pitch
yes no well four
yes no well four
yes no well four
Figure 4. 17
yes no well four
yes no well four
(Roach 2009, p.192 Audio Unit 15, Ex 1)
1) The accentual function
to indicate the focus of the information
2) The attitudinal function
to indicate the speaker’s attitude
3) The grammatical function
a. Statements: falling tone
Most native speakers of English can, for example, recognize people from France by their French accents. ↘
Figure 4. 19
b. Wh- Questions: normally falling tone
Why do people usually have an accent when they speak a second language? ↘
c. imperative sentence: falling tone
Please sit down. ↘
d. Yes/No Questions: normally rising tone
Does this mean that accents can’t be changed? ↗
e. Listing: combination of rise & fall
I like apple, ↗ cherry，↗ and banana.
f. Tag questions: rising and falling tone
Falling tone à the speaker is quite certain, only seeking confirmation / agreement
Rising tone à the speaker is unsure, a genuine request for more information
But old habits won’t change without a lot of hard work, ↘ will they? ↘
But old habits won’t change without a lot of hard work, ↘ will they? ↗
g. Closed-choice alternative questions: combination of rise & fall
Will you manage to make progress, ↗or will you just give up? ↘
Figure 4. 26
Figure 4. 27
As mentioned in 4.3, tone is the pitch of our voice. In Chinese, a syllable or morpheme may have its own pitch, and the tone of each character contributes to lexical meaning while in English, a series of pitches sung over a whole utterance (intonation) is the major prosodic features to indicate the meaning (Teschner & Whitley, 2004, p.64). Therefore, ‘pitch’ is mainly used to analyze the tone.
Tone is a contrastive lexical property of Standard Chinese. As a tone language, there are five tones in mandarin Chinese --the first tone, the second tone, the third tone, the fourth tone and the neutral tone. We can use the “pitch” in Praat to analyze the tones in Chinese.
The diagram below shows four tones in Putonghua.
Excerpt from http://web.mit.edu/jinzhang/www/pinyin/tones/
Let’s take “ma” in Putonghua for example, five tones represents five different characters which have different meanings
Figure 4. 29
Figure 4.30 Four Chinese tones
As we know that Cantonese is another tone language which has 9 tones (the last three tones share the same pitch with first, third and sixth tone respectively)
you can listen to the sounds via the following website http://www.fyan8.com/yuepin.htm
We can also use Praat to show the six tones in Cantonese.
Figure 4.31 Six Cantonese tones
Excerpt from http://bbs.cantonese.asia/thread-15985-1-1.html
Now let's discuss how we analyze tone using Praat. We will use a recording of the four Standard Chinese words as an example.
1. Created a WAV file with four Chinese words mā `mother', má `hemp', mǎ `horse', and mà `scold'
2. Selected the file and click View& Edit,
3. Pitchàtick Show pitch
The window is like this:
This window provides us with a graphic presentation of the variation in fundamental frequency (pitch contours) of the four Chinese tones
4. Adjust the pitch settings to make the display clearer.
I just briefed two important points here:
(Please see 1.4.3 for more details on measuring pitch)
(Retrieved from Stoneham, 2011: p2, http://stonham.dyndns.org/phonetics/handouts/prosod_hndt.pdf)
5. Draw the pitch contours
(Please see 1.3.4 for more details on drawing pitch contours)
1. What stands for “stress” in Praat?
2. Is the duration of the stressed syllable longer or shorter than the unstressed?
3. Put the stress marker in “record” according the following two pictures.
4. Which one is the noun of “contrast”?
5. Mark the stressed syllables in each word with capital letters according to the pitch contour in the spectrogram and tell the reason in simple words.
6. Which sentence does the following picture belong to?
A. I will go to the supermarket tomorrow. B. What’s your name?
C. I like apples, cherries and bananas. D. Do you like this one?
7. How do you measure the VOT in Praat?
8. List the major types of linking and explain how you measure them in Praat.
9. What stands for “intonation” in Praat? How do you observe the intonation in Praat?
10. What’s the difference between rising and falling tone of tag questions?
(See the suggested answers at the end of the manual)
Styler, Will. (2014). Using Praat for Linguistic Research.
Stonham's lecture notes (2011), retrieved from http://stonham.dyndns.org/phonetics/handouts/prosod_hndt.pdf