- Dr Akamo O. Princewill
- NAS Journal of Education, Linguistics and Literature (NASJELL)
This
present study acoustically compares two central vowels of English, that is, the
mid-central short vowel /ə/ popularly known as schwa, and the mid-central long
vowel /ɜː/ which linguists refer to as NURSE sound, as realised in Received
Pronunciation (RP) and Educated Nigerian English (NigE). Analysis centres on
realisations of the two centralised mid-vowels (short /ə/ and long /ɜ:/) in the
chosen corpora. Spectrographic analysis of formants in the target words:
brother, butter, discussion, bird, early and journal estimates differences in
first and second formant frequencies, amplitude, temporal realisation and
overall spectral shape. Fifty speakers (25 RP reference speakers and 25
educated Nigerian English speakers) produced the words in word-list and
sentence reading frames; data underwent Praat spectrographic analysis. Results
show that RP speakers maintain a centralised /ɜ:/ with rather low F1 and
intermediate F2 values, and a highly reduced schwa can also be observed. NigE
speakers consistently de-centralised, replaced or substituted both target
vowels, producing a substantially elevated mean /ɜ:/ F1 by 164 Hz and a 136 Hz
increase for centralised schwa. Evidently,
the duration dissimilarity between short centralised vowels is considerably
narrower in the NigE variety. The differences in this duration difference
influence intelligibility and shape the description of Nigerian English as an
endonormative variety. In the mixed-method research design, depict divergence
through quantitative formant frequency data, and through qualitative listening
and spectrographic analysis of amplitude, duration and overall shape. This
method reveals the array of differences, in the centralised short‑vowel
realizations of the two English dialects.
Keywords: Central
vowels, formants, Received Pronunciation, Educated Nigerian English, Praat
Spectrographic analysis