Materials

1. Introduction Previous instrumental work on prosodically-conditioned consonant allophony has adopted a distinction between two types of articulatory gesture. More radical constrictions are known as consonantal gestures. Less radical gestures are known as vocalic gestures. For example, a retroflex /r/ may have a front lingual consonantal constriction and labial and tongue-back vocalic gestures. In predictable ways, the syllabic context of a consonant alters the magnitude of these gestures to different degrees, and alters their relative timing. It seems that it is in onsets that consonantal gestures exhibit their characteristically large magnitude. They tend to be early relative to the smaller magnitude vocalic gestures. In codas, vocalic gestures have relatively greater magnitude and they are the ones which tend to be timed early, relative to the gesturally-weakened consonantal gestures. Intervocalic consonants are often characterised as being ambisyllabic when phonological and phonetic criteria do not uniquely specify them as being onsets or codas. Gick (1999) claims ambisyllabic allophones will display articulatory patterns intermediate between the onset and coda extremes. Word-final consonants alternate. In isolation, or before certain consonants, they are codas. But before a vowel (i.e. a vowel-initial word), they may have onset-like characteristics, so are often said to be ambisyllabic. In some cases, these post-lexical alternations become historically systematised, such that phonologists have analysed word-final consonants as being resyllabified from the citation-form coda to connected speech onset. One such case is the r-sandhi of most varieties of non-rhotic (r-less) British English, in which car seat has no audible [r] but car engine does. According to traditional descriptions, this phenomenon is categorical in two respects: the linking /r/ in such analyses is an onset, and there is no /r/ in codas at all. This connected speech alternation of /r/-final words is highlyproductive. It can be analysed as a syllabic constraint on the presence or absence of /r/. An articulatory analysis following Gick would be that word-final /r/ is in fact present in car seat, albeit with radically reduced consonantal gestures. Such an analysis captures similarities between the vocalic gestures of /r/ and the vowels that replace it when it is apparently deleted. On this view, linking /r/ isambisyllabic. The consonantal gesture of word-final /r/ would be smaller in magnitude than word-initial onset /r/ in comparable phonetic contexts. Moreover, the inter-gestural timing of the C and V gestures would be different in onset /r/ and ambisyllabic linking /r/: vocalic gestures ought to be more advanced (relative to the consonantal gesture) in linking /r/. And finally, rhotic and non-rhotic English would differ by degree, not by type. Pilot study using the MOCHA-TIMIT corpus All sentences containing /r/ in the 460 sentence phonetically representative MOCHA-TIMIT corpus (Wrench and Hardcastle 2000) were evaluated for measurement. The corpus comprises acoustic, EPG, laryngographic and EMA data gathered from a range of accents of English (including L2 learners). As well as being a pilot study of r-sandhi (Mullooly in preparation), we intended to explore the utility of the corpus as a labphon linguistic research tool. Primarily designed as a speech technology tool, the corpus provides a wide variety of contextualised phones. It was very useful for examining EMA data of /r/ in different phonetic contexts and accents, and for studies of large effects, but less so for subtle phonetic differences. An EMA study of [r] in non-rhotic English • Results • TT Retraction (location)The rhoticcontrolsdo have a difference in TT position conditioned by syllabification F(2,101)=3.74, p<0.05. There are no subject effects. Post-hoc tests show onset /r/ differs from coda /r/, but that ambisyllabic /r/ (which is intermediate) is not significantly distinct from either. No difference between onset /r/ and linking /r/ was detected for the non-rhoticsubjects. All three differ from each other, however, in the absolute value of TT location (though msak and maps only differ in onset /r/.) For all subjects, variability is high, with onset /r/ varying most. • Among the non-rhotics, only msak shows a tendency for greater retraction in onset (below left). The wide lexical, segmental and prosodic variation in the materials may be responsible for this tendency being insignificant. His positional data seems similar to the rhotic speakers (below centre and right). But the other non-rhotic subjects’ tendency is the reverse. Further research with specialised materials is underway (Mullooly, in preparation). • We found no evidence that a residual TT gesture is present in cases where the /r/ is not audible in the non-rhotic speakers. • TD and LL positionNo differences due to syllabification were found. • Inter-articulator timingNo timing differences were found with respect to syllabification. It is possible that the American speakers have an earlier TD gesture, perhaps indicative of a darker acoustic quality to their dialects’ /r/. • Summary • We examined the hypotheses that /r/ comprises consonantal and vocalic gestures and that they differ in their extent and relative timing in different syllable roles, by analysing EMA data from a phonetically varied corpus. • Two rhotic speakers gave partial support: /r/ has a stronger TT gesture in onset than in coda. Non-significant evidence of ambisyllabicity was found. • From the three non-rhotic subjects we tentatively infer that linking /r/ is in the onset, as traditional accounts suppose, and is not ambisyllabic. Alternatively, non-rhotic systems may show inter-speaker variation. Rhotic speakers Non-rhotic speakers • Examples of ambisyllabic sentences • Swing your arm as high as you can. • Pizzerias are convenient for a quick lunch. • Are you looking for employment? • May I order a parfait after I eat dinner? • Jeff thought you argued in favour of a centrifuge. • Examples of onset sentences • He will allow a rare lie. • A roll of wire lay near the wall. • Get a calico cat to keep the rodents away. • Chocolate and roses never fail as a romantic gift. • Good service should be rewarded by big tips. • Examples of coda sentences • Movies never have enough villains. • Does Hindu ideology honour cows? • We apply auditory modelling to computer speech recognition. • Remember to allow identical twins to enter freely. • How ancient is this subway escalator? • Geminates etc. • We excluded (1) gemination, (2) ambiguity or (3) syllabic /r/. The articulatory analysis requires that non-rhotic English never contains word-final non-high vowels: All contain /r/. • brotherrepainted, afterRachel, barracudarecoiled • corner off, herarrange • her early (US rhotics only) Richard MulloolyJames M. ScobbieAlan A. Wrench Labphon 2002 Definition of “retraction” The distance from the fixed UI ref coil to the TT coil. Number of tokens Pooled rhotic speakers: onset n=31 ambi n=45, coda n=25 Pooled non-rhotic speakers: onset n=46, ambi n=63 Individual differences in appearance of linking /r/ Non-rhotic speaker fsew avoided linking /r/ on many occasions, providing only 10 tokens. This was not gradient gestural weakening, but stylistic avoidance of linking /r/. In these non-rhotic cases, TT was about 15mm anterior to an [r]. Intrusive /r/ The non-rhotic subjects have non-etymological sandhi (there is an [r] in draw it). The vowel contexts in the corpus did not permit analysis here. See Mullooly (in preparation). Other observations The non-rhotic subjects’ laterals alternate: the coda ones are vocalised and the ambisyllabic ones generally have contact. Corpus and EMAtools are available to researchers Contact awrench@qmuc.ac.uk • Materials • The corpus of 460 sentences provides examples of /r/ in many prosodic, sentential, lexical and segmental contexts, but there are no repetitions. All speakers spoke the same sentences, so cross-speaker comparisons can be easier than cross-contextual comparisons, which exhibit a great deal of token-to-token variability. Enumeration and evaluation of the contexts containing intervocalic /r/ led us to choose a context in which /r/ was likely to be preceded by a weak vowel. In most cases it was also followed by one. • Onset: Word-initial prevocalic /r/ following weak vowel • Ambi: Word-final prevocalic /r/ following weak vowel (potentially ambi) • As a control, two rhotic speakers from the USA were examined (faet & mjjn). In addition to onset and ambisyllabic /r/, it was possible to investigate obligatory coda /r/ for these speakers, though this /r/ was not intervocalic. • Coda: Word-final pre-consonantal or pre-pausal /r/ following weak vowel • The subjects were three non-rhotic speakers from England (fsew, msak & maps). • Annotation was done in MATLAB using Wrench’s enhanced version of Nguyen’s EMAtools. Annotation points were identified using the tangential velocity of coils attached to the lower lip “LL”, tongue tip (about 7-10mm behind the tip) “TT” and tongue dorsum (about 3-4cm posterior to the TT coil) “TD”. The time of the minima was recorded, along with x and y positions of the relevant coil. Locations at peak velocities in and out of the /r/ constriction were also recorded. (See xy charts in results section.) • In this example of onset /r/, the TT speed min (middle) indicating target attainment precedes both the LL min (top) and the TD min (bottom). Gick, Bryan (1999) A gesture based account of intrusive consonants in English, Phonology 16:29-54. Mullooly (in preparation) An instrumental study of alternating [r] in non-rhotic English dialects. PhD Thesis, QMUC. Wrench, Alan and Hardcastle, William J. (2000) A multichannel articulatory speech database and its application for Automatic Speech Recognition. Proceedings of the 5th Seminar on Speech Production: Models and Data & CREST Workshop on Models of Speech Production: Motor Planning and Articulatory Modelling. 305-308.