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8
Differential Acoustical Cues for Palatalized vs
Nonpalatalized Prevocalic Sonants in Lithuanian
The lowest values for the F2 locus in nonpalatalized
cases were found for [m], followed by [l], [n],
and [r]. This is not surprising since this succession
corresponds to the step-by-step posterior movement
of the constriction; from labials to alveolars or postalveolars,
i.e., in a sense, a plain [r] is more ‘palatalized’
than a plain [m]. What is more interesting is that
dental [l] shows a statistically negligible difference
from labial [m]. A possible explanation is that, at least
for the speaker examined, the corresponding places
of constriction do not differ much, and, in the case
of [l], the tongue makes a significant excursion to
the uvula or lower, thus lowering F2 (refer to Figure
1). This articulatory difference is also reflected in
the significant rise of F3 for [l] for the same reasons
(see the rise of F3 when the (secondary) constriction
moves to the uvula or lower, Figure 1).
In addition, plain (nonpalatalized) [n] seems more
retracted, i.e., moved into the direction of apicoalveolar
position, compared to [l].
For palatalized consonants, F2 loci show the
highest values for [n’], followed by [r’], [l’], and
[m’]. Thus [n’] is the most ‘soft’, and this can be
ascertained simply audially. It results from the natural
‘comfortable’ configurations of the tongue, which
differ according to the different consonants (here we
will not discuss this issue in detail).
More information could be extracted from Figure
2. Here we will limit ourselves to two additional observations.
First, for [m’], a certain separate subclass
characteristic of high F2s and F3s is formed. It is
mostly associated with a distinct change of articulation
in [m’ė] or [m’i]-type syllables ([m’] becomes
extremely palatalized – at least, in the case of the
speaker examined). Second, F2s for [r] and [r’] are
not separated as much as for other consonants; even
a slight overlap is registered. Inter alia, it seems that
sometimes the speaker tends to ‘strengthen’ [r’]s,
making them harder.
One can expect that the impact of the place of
articulation onto loci should be similar for different
homorganic sounds. For instance, most probably,
F2 loci for homorganic sonants and stops should
coincide. Loci for stops have been examined in
numerous studies; Figure 3 presents a comparison
with the evaluations for stops made by Kewley-Port
(1983).
At first glance, it might seem that the F2 values
for nonpalatalized sonants in the present study are
unnaturally low. However, we should remember that
Kewley-Port examined English consonants. In the
Lithuanian case, the distinction between palatalized
and nonpalatalized consonants is made stronger, thus
Diferenciniai akustiniai palatalizuotų ir
nepalatalizuotų prevokalinių lietuvių kalbos sonantų
požymiai
the F2 loci for plain consonants are moved to lower
values, in a sense, to keep a distance from their palatalized
counterparts. In English, palatalization does
not form opposite consonant pairs. For the Lithuanian
ear, English alveolar stops sound semipalatalized,
and Figure 3 visualizes this phenomenon.
Figure 3. Left: F2 loci for prevocalic sonants (higher:
palatalized; lower: nonpalatalized). Medians (diamonds)
Figure 3. Left: F2 loci for prevocalic sonants (higher: palata
and interquartiles (vertical lines) are depicted. Right:
nonpalatalized). rough evaluations Medians for stops; (diamonds) after Kewley-Port, and interquartiles 1983. (vertical lines)
Right: rough evaluations for stops; after Kewley-Port, 1983.
Effect of vowels (regressive
coarticulation)
At first glance, it might seem that the F2 values for nonpalatalized
present study are unnaturally low. However, we should remember tha
examined It is known English that loci consonants. are far from In the invariant; Lithuanian they case, the distinc
depend palatalized on and the nonpalatalized phonetic context consonants (for instance, is made stronger, see thus the F2
the typical work by Öhman (1966)). One can derive
consonants are moved to lower values, in a sense, to keep a distan
the loci frequencies as the functions ‘of the vowel’s
own
palatalized
intrinsic,
counterparts.
target formant
In English,
frequency’
palatalization
(‘locus
does not form oppo
equations’; pairs. For the Howie, Lithuanian 2001, ear, 2). English Figure alveolar 4, in the stops manner sound semipalatalized
similar visualizes to the this one phenomenon. presented by Öhman, demonstrates
this dependence (on the succeeding vowels) extracted
from the data examined in the present study. The
tense (‘long’) Effect and of vowels lax (‘short’) (regressive vowels coarticulation) are combined
into joint classes. It should be noted that, generally,
back vowels It is known result that in loci lower are far F2 from loci invariant; compared they to depend on the ph
front
(for
vowels.
instance,
However,
see the typical
some
work
permutations
by Öhman
among
(1966)). One can d
vowels are also noticeable. This has several explana-
frequencies as the functions ‘of the vowel’s own intrinsic, target form
tions; here we will mention only two of them. First,
certain (‘locus Lithuanian equations’; Howie, vowels 2001, have 2). only Figure tense 4, in versions. the manner similar to the
This explains why [ė] (tense) frequently results in
higher F2s compared to [i] (averaged tense and lax
versions), and [o] (tense) frequently results in lower
F2s compared to [u] (averaged tense and lax versions).
Second, the influence of the specific speaker
and the limited statistical sample could be at work.
Rytis AMBRAZEVIČIUS