Me. Lehman et B. Swartz, Electropalatographic and spectrographic descriptions of allophonic variants of vertical bar l vertical bar, PERC MOT SK, 90(1), 2000, pp. 47-61
Prevocalic and postvocalic /l/ were investigated in three adult subjects ut
ilizing a combination of electropalatographic and acoustic techniques. Resu
lts indicated that prevocalic /l/ was characterized by both alveolar and la
teral lingua-palatal contact, while postvocalic /l/ was primarily alveolar
contact only. Acoustically, prevocalic /l/ had a lower first formant and hi
gher second formant than postvocalic /l/. In addition, the second and third
formants were often weak or absent for prevocalic but not postvocalic /l/.
Vowel context had a greater effect on the electropalatographic and acousti
c characteristics of prevocalic than postvocalic /l/. Models that relate ph
ysiological and acoustical aspects of speech were utilized to account for t
he observed results.