Nasal voices in accents of English: Aeroacoustics, sociolinguistic variation, and forensic application

When a person speaks, their accent will differ along a number of dimensions. This includes their
production of different vowels or consonants, specific intonation patterns, and also overarching
aspects of voice quality, such as a creakiness (Laver 1980). For some individuals, or in particular
dialects, an overarching nasal quality across all speech sounds can sometimes be heard. While all
English speakers produce nasal sounds in words spelt with 'n' or 'm', nasal voice quality refers to a
property of all speech sounds achieved by air habitually resonating in the nose as well as in the mouth.
While aspects of accent such as vowels and consonants are well-studied in the sociophonetic
literature, comparatively little is known about voice qualities such as overarching nasalisation. This is
a clear gap in terms of the knowledge forensic speech practitioners require in order to perform
casework assessing possible dialectal origins of suspect recordings. The project will utilise a
combination of cutting-edge phonetic tools including nasal air flow, acoustic and auditory methods,
and advanced statistical and computational analysis. The primary aim of the research is to inform the
study of sociolinguistic variation from a phonetic perspective, whilst having impactful implications for
forensic linguistics.