Assignment 3

LINB09H3F Phonetics

Waves

1.  Examine the wave shown below.

(a)  What is the amplitude of this wave?

(b)  How long is one cycle of this wave?

(c)  What is the frequency of this wave? Show the formula you used to calculate this. Give your answer as a whole number or decimal, with the correct units.

2.  Examine the oscillogram below of a disyllabic word and answer the following questions.

(a)  Circle a periodic waveform. above and label it “P”.

(b)  Circle a stop in the word above and label it “S”.

(c)  Which syllable would a listener perceive to be louder?      first     second

(d)  Which syllable would a listener perceiver to have a lower pitch?    first      second

Spectrograms

3.  Examine the spectrogram below and answer the following questions.

(a)  What type of spectrogram is this?

(b)  Is the f0  of the sound rising or falling?

(c)  What is the f0 at the point where the vertical line is drawn?

(d)  What English word could this be a spectrogram of?  (It’s hard to tell for certain but there are a variety of plausible options.)

Examine the paired waveform. and spectrogram below for the questions 4 & 5. This figure shows the word [skiɾʲɪzdʌmʌs] ‘when flying’ in Lithuanian, a language from the Baltic branch of the Indo-European family, spoken by approximately 3 million people in Lithuania.  Note that the breve diacritic [ ̆ ] here indicates an extra-short vowel. Formant estimates from Praat’s formant tracker algorithm are shown on the spectrogram with the red dots, and the waveform. and spec- trogram are divided into segments with dashed lines and numbered as an aid for you.

4.  Indicate segments matching each description by writing their number(s) on the blanks. Try to choose the clearest examples you can.

(a)  Two segments that consist solely of a periodic wave

(b)  Two segments that consist solely of an aperiodic wave

(c)  One segment that consists of a combination of a periodic and aperiodic wave

5.  The two vowels transcribed as [ʌ] above (segments 8 and 10) are not being produced in exactly the same place in the mouth.  What is one difference in their articulation in this utterance, and how can you tell?  If we wanted to make the IPA transcription narrower to reflect this difference, how could we do this?

Phonetic measurements

Download the sound file A3.wav from Quercus and open it in Praat. This sound file contains the following four words from Telugu (a Dravidian language spoken by nearly 100 million people in southeastern India):

The words in A3.wav are in the order shown above. Telugu has long and short vowels and also long and short consonants, as indicated in the phonemic transcriptions given. For each word, you will be measuring the durations of the first vowel and middle consonant, and the formant frequencies of the first vowel.

You should examine both the waveform and the spectrogram of this audio to answer the questions below,  and listen carefully to the parts of the sound that you select to make sure you’re on the right track!  When taking your measurements, keep in mind our dis- cussion about sonorants having periodic waveforms.  You might also want to review the concept of VOT from Lecture 7:  we generally measure the duration of stops up until the voicing/periodicity of the vowel begins. You should record your measurements in millisec- onds, as this is typically how segment durations are reported in linguistics.

For optimal visual contrast, set Dynamic range (dB): 55.0. Note that there is a bit of echo in the recordings so there may be some light grey wispy colour even during silences.  (You can hear this echo if you select a stop closure and listen to it.)

6. Research question 1: In Telugu, how much longer are long segments than short segments? As we did in this week’s tutorial (T6), measure the duration of the first vowel in each word (/o/ & /oː/) and the second stop in each word (/t/ & /ʈː/). For each category (short vowel, long vowel, short stop, long stop), once you have both measurements, average them together into a single number. Write these on the blanks below:

How long are short mid-high vowels in Telugu, on average? ms

How long are long mid-high vowels in Telugu, on average? ms

How long are short coronal stops in Telugu, on average? ms

How long are long coronal stops in Telugu, on average? ms

(Disclaimer: We are simplifying a little here!  Normally, we’d want to average together waaay more than two measurements to make a generalization about the sounds.  We’re also assuming that the durations of the two types of coronal stops are equivalent: normally we’d want to compare short and long stops of the exact same place of articulation, like /t/ and /tː/.)

7. Research question 2: What is happening with Telugu mid vowels? You might have noticed that the first vowel in /koːti/ ‘monkey’ and /poʈːu/ ‘husk’ sounds slightly different from the first vowel in /koːta/ ‘cut’ and /poʈːa/ ‘tummy’. These vowels are the same phoneme (and are even written the same, with for short /o/ and for long /oː/).  However, there is vowel allophony in Telugu: vowels are produced slightly differently in syllables before /a/!  Let’s see what is different.

First, make sure your formant tracker is turned on (red dots are visible). If not, go to Formants

Formants    Show formants .   Then, just in case,  double-check that you are correctly using the default formant tracker settings by going to  Formants     Formant settings  and clicking  Standards . Use Praat to measure the first and second formants of the /o/ and /oː/ vowels.  Rather than estimating visually, let’s get Praat to measure the average formant frequency of the vowel: select the entire vowel and press   F1   for F1 and   F2   for F2.  Write these down for yourself and then record the average of the two formant measurements below:

F1 F2

/o, oː/ before /i, u/ Hz Hz

/o, oː/ before /a/ Hz Hz

8. Discussion: What generalizations can you make about the formant differences you found in Telugu mid vowels?  (Hint:  keep in mind that variation of 10–15 Hz in formants is quite minor.) What do your measurements tell you about the articulation of /o/ vowels before an /a/ vowel? Why do you think this might be happening? Use correct terminology and explain your reasoning.