Discussion Of The Effect Of Three Emphatic Consonants On The Egyptian Arabic Eight Vowels With Respect To Acoustic Vowel Space Area
The purpose of the present experiment is to investigate the effect difference of three emphatic consonants /tÞ/, /sÞ/, and /q/ on the Egyptian Arabic eight vowels with respect to acoustic vowel space area, taking into account the differences in age and gender using large number of speakers.
From our results we can say that the acoustic features which reflects the effect of emphatic sounds is the slight rising of F1 and the explicit lowering of F2. In details we can say that F1 T test results show that there is a significant increase in F1 in the three emphatic environments. In males F1 increases slightly in five vowels among the eight CEA vowels in the two environments; alveolar and uvular: /sÞ/, and /q in other words they have the same impact pattern; where they affect the four vowels /u:, o:, e:, i/ which are playing as a common factor between the two emphatic environments. And only three vowels in dental environment /tÞ/. on the other hand in children the effects of three emphatic environment is very minor ; only three vowels /a:, a, i/are affected in consistent way; in other words F1 increment is redundant and don’t give any specific rule.
F2 T test results show that there is a significant decrease in F2 in the three emphatic environments. In males F2 decreases clearly in seven vowels among the eight CEA vowels in the all three environments; dental, alveolar and uvular. The four vowels /a:/, /a/, /i/, /u/ are playing as a common factor between the three emphatic environments. For females F2 T test results show that there is a significant decrease in 6 vowels in /t/ environment and seven vowels in alveolar and uvular environments. The six vowels /a:/, /i:/, /e:/, /a/, /i/, /u/ are playing as a common factor between the three emphatic environments. We can conclude that especially in adult females the second formant of the long back vowel /o:/ is never affected in the three emphatic environments, while the long back vowel /u:/ is never affected alveolar and uvular environments. In children the pattern of F2 decrease is not consistent between the dental and alveolar emphatic contexts, while in uvular environment F2 is lowered in the same pattern where back vowels are never affected by uvular emphatic consonant. According to T test results the long back vowel /o: / is never affected by the three emphatic vowels. The long back vowel /u: / is not affected in most emphatic environment in males and female children. Sometimes it is affected in alveolar environment in male children and dental environment in female children.
Because the main concern of the present experiment is to illustrate the difference between the plain space and emphatic one, we will introduce a global summary of the result scatter plots. With respect to scatter plot F1 vs. F2 the matter is almost clear (restricted), As when comparing between F1 and F2 measurements and to what extent they are influenced by the preceding emphatic consonants, we will find that emphasized acoustic vowel space seems to be smaller than plain vowel space, because of the F2 small values of the three vowels [a:], [a] and [i] which play an important role in changing the vowel space area, with focusing on short [i] which is the main reason of reducing the emphatic vowel space. This form of changing vowel quality occur in the four groups; adult males, adult female, male children, and female children. Similar acoustic characteristics have been observed for some emphasized vowels in Norlin study (1987) where F1 raises slightly and F2 lowers. As illustrated in the scatter plot figures, the plain acoustic vowel space looks like a semi-triangle, its base is at the top, and the vertices of this base are the long vowels i: and u:, and its apex is at the bottom represented by the short vowel /a/. When vowels are emphasized, the F2 values of the three vowels /a:, a, i/ are largely decreased, as a result the triangle moves clearly to the back (F2 decrease), and slightly to the down (F1 increase). Accurately the left side of the triangle is broken and pulled out to the back to make a new vertex which called an emphasized [iÞ], in addition long vowel /a:/ is transported from left side of the triangle to the right side. This means that in emphatic context the distance between F1 and F2 of the short vowels is smaller than those in plain ones, since the small distance mainly due to F2 decrease not F1. In other words F2 is the main clue that indicates the influence of emphatic place of articulation, this result accords with Wahba (1988), and does not accord exactly with El Dalee (1984) as he stated that main clue of retraction (emphasis) is the decreasing of F2 and increasing of F1 at the same time and also raising of F1 and F2.
About the role of the first and second formants; our results makes the second formant in the foreground of making emphasized vowels, after the second formant the first one comes ; which has a very minor role in this phenomenon. The clear evidence for this explanation arise from T test male children results where F1 has no significant difference between plain values and emphasized ones for all vowels in uvular environment, therewith the F1 vs F2 scatter plot looks like the ones of the adult males and females as there is a very clear difference between plain and emphasized space. This means that F1 is not a distinctive parameter in making emphasized vowel; its role is very petit or secondhand not basal at all. This result doesn't accord with El Dalee result (1984).
To conclude, emphasized acoustic vowel space seems to be smaller than plain vowel space; this reducing is mainly due to small values of the short vowel F2 /i/; no one up to my knowledge refer to that short vowel /i/ is the main reason in changing the emphasized vowel space area. The most affected sound with emphasis is the long vowel /a:/; this result does not accord with El Dalee (1984) as he refer that the most affected one is the vowel /a/ followed by /i/ followed by /u/ in general without determining if they are long or short, as he considers them carry the same quality and added to them the two mid long vowels /e:/ and /o:/, as he stated " phonemically, there are five vowels with regard to quality. The vowels /e:/ and /o:/ have no short counterparts, but other vowels: /a/ /i/ /u/ have their long counterparts". He does not deal with them as six distinct phonemes with respect to quality, so the system for him is five vowels, for his way of analysis, his results are differ from ours as he arranged the vowels in according to the strength of retracted allophones as follows:/a/ shows the most influenced and /i/ shows a fair amount of influence and then /u/ which has the least distinction. comparing his result with ours illustrates very important differences where /a/ for him is actually two phonemes for us : the long /a:/ and the short /a/ with two different results where the long /a:/ is the most affected by emphasis followed by short /a/ then short /i/ which affected clearly with emphasis and not long one at all. If long /i:/and short /i/ have the same quality as El Dalee states, they have to respond to the phenomenon in the same way. the explanation of sensitivity of /a/ either the long or short can be explained according to Al-Ani (1970) who refers to vowel /a/ as low central vowel which is easily affected by any advancement or retraction. Also, the /a/ stricture is the nearest one to pharyngeal cavity.
Conclusions
Among all EA vowels, the most affected ones by emphatic consonants /tÞ/, /sÞ/, and /q/ are the vowels; [a:], [a], [i] sequentially. The long vowel [a] is the most emphasized vowel in EA, and therefore characterized by the lowest F2 which is compatible with emphatic production. The long vowel /a:/ is emphasized by all selected groups adult males and females, as well as male and female children. The difference between plain and emphasized vowels with respect to F2 frequency was much greater than that for F1 in the three emphatic consonants /tÞ/, /sÞ/, and /q/. i. e F2 is the main reason of reducing the acoustic vowel space of emphasized vowels. The common factor between three groups of emphasized vowels is that F1 is slightly affected in children; the maximum effect extends to two vowels no more than this.
