PHONLINE Report

2.1 Voiced and voiceless sounds

The consonant sounds of English — and of languages generally — are not just a random assortment of different sounds. As the grid layout of the IPA chart suggests, each consonant can be classified according to a small number of separate properties which together describe its production. The most important of these are voice, place and manner of articulation.

All speech sounds are either voiced or voiceless. We speak while breathing out, and as air passes through the larynx on its way from the lungs, we can either

• vibrate the vocal folds (vocal cords), producing a buzzing tone of definite pitch, which results in voiced speech sounds, or
• keep the vocal folds apart, so that air flows between them without making them vibrate, but then encounters resistance and obstruction on its way out of the mouth, giving voiceless sounds.

Examples of voiced sounds are English consonants such as [m n l w r z v], and also all English vowels and diphthongs. Examples of voiceless sounds are the English consonants [f s p t k h].

Like many languages, English makes use of the voicing contrast to distinguish otherwise identical consonant sounds. For example, the sounds [f] and [v] are alike in all respects except that [f] is voiceless and [v] is voiced. If, on a single breath, you alternate prolonged versions of the two in an uninterrupted sequence [fvfvfv], you should be able to feel, and to hear, that vocal fold vibration (voice) switches on for every example of [v], and off again for every [f].
LA211

Figure 2_1. Waveform and spectrogram for [fvfvfv]: adult male speaker.

Voiced and voiceless speech sounds show characteristic differences when we examine their waveforms and spectrograms. Figure 2_1 shows the waveform and spectrogram for the [fvfvfv] sequence, with the speaker switching at intervals of about one second. There is continuous energy, indicating that there are no gaps between the sounds, but two different patterns are being alternated. The sequence starts with voiceless [f]. For this portion, the waveform is small and irregular, while the spectrogram shows a wide scatter of energy, but none at the very bottom of the frequency scale (the frequency scale is the vertical or y-axis). When voicing switches on for [v], the waveform becomes much larger. The spectrogram shows that the wide scatter of energy continues, but now with the addition of a strong band at the bottom of the frequency scale, which is striped (striated), corresponding to the regular pulsing of the vocal folds. In fact, they are vibrating at about 115 Hertz (Hz).

Zooming-in on the one of the places where voicing switches off in this sequence, we see how the large fairly regular wave of the voiced sound gives way to the smaller random waveform of voiceless [f].

Figure 2_2. Switch from voiced to voiceless in [fvfvfv] (enlarged)

There are in total 24 English consonant sounds. Sixteen of these are in voiced/voiceless pairs. In the following array, the top line consists of voiceless sounds; the lower line shows the corresponding voiced sounds.

Only one English sound is voiceless without any voiced counterpart, and that is [h]. Then there are seven which are voiced, without any voiceless counterpart, and they are:

Assignment 1 FEEDBACK

• The main purpose of Assignment 1 was to practise using phonetic symbols in PHONLINE assignments, and familiarize you with making a submission and receiving feedback. If you feel that you have learned something from the process, then the assignment has been a success.


• A number of assignments contained confusions between somewhat similar-looking symbols which probably result from putting them into the document by the cumbersome Insert Symbol method rather than from the keyboard. For example:

  ɘ wrongly for schwa ə ;
  ɵ wrongly for theta θ ;
  ` wrongly for stress mark ˈ .
  

  If you are a PC user, you are strongly urged to install the Unicode Phonetic Keyboard (see "Getting Started"). This will automatically save you from most such mistakes.


• (No marks were deducted for this small point). We don't mark a stress on a one-syllable word in isolation. Conversely, if we look in a dictionary and see a word marked with a stress, that means that the word is regarded as having at least two syllables, even when that is otherwise not clear. For example, in OALD you will find fire transcribed /ˈfaɪə/, complete with a stress mark. The inclusion of the stress mark indicates that the editor believes the word has two syllables (not one, as might quite reasonably be thought).
  
  Of course, a monosyllabic word may get a rhythmic stress in connected speech — but in this exercise, we are transcribing isolated words.

1. Give the following words in ordinary spelling (orthography). Transcriptions are given in RP.

   1. fəˈnetɪks	phonetics
   2. ˈɔ:θə	author
   3. kwi:n	queen
   4. wi:v	weave
   (also the pronunciation of we've, though it is debatable whether that is one word or two)
   5. əˈpru:v	approve
   6. ˈbʌni	bunny
   7. θɔ:t	thought
   8. əˈtend	attend
   9. praɪs	price
   10. bɪˈfɔ:	before