This chapter examines voice quality as the long-term, relatively constant or habitually recurring phonetic characteristics of an individual’s speech. The identification of voice quality settings relates the auditory/acoustic components of the voice quality strand of an individual’s accent (i.e. habitual manner of speaking) to the articulatory postures or movements that shape speech sound quality over the long term. An essential generator of long-term quality is the larynx, producing sustained vibrations and laryngeal articulatory resonances that interact with vowel quality and tonal quality. Various instrumental phonetic procedures have been developed to observe postural settings of the parts of the vocal tract. The images from these experimental observations have been incorporated into instructional tools for teaching and learning about voice quality settings and the movements of the laryngeal articulatory mechanism in particular.

Chapter 4 contains extensive references to exemplifications of the voice quality categories described in Chapters 1 and 2. Distinctive voice quality settings of actors, singers, media announcers, politicians, and other personalities are cited with specific references to be used as search terms to locate video and audio material online. A separate ‘Multimedia References’ section is included at the end of the text to facilitate searching. Long-term voice qualities are essentially extralinguistic, but they can also alternate among phrases of speech as paralinguistic ‘registers’. Many laryngeal postures, and their auditory output, are employed linguistically as syllabic registers or segmental units to signal contrastive lexical meaning. This is a result of the positioning of the laryngeal articulator at the beginning of the shaping of the sound stream, where background elements are easily patterned behind oral articulations. Extensive references to linguistic examples of lower-vocal-tract consonantal strictures and tonal register effects are presented within the text notes and are included among the video and audio materials online.

Chapter 7 explores laryngeal speech disorders, voice pathologies that depart from normal function, and the consequences of laryngeal surgery on voice quality from the perspective of the Laryngeal Articulator Model. Clinical cases involve the laryngeal mechanism as a whole, and many voice quality outcomes resemble the registers of linguistic systems. New drawings diagram surgical excisions of laryngeal structures. Post-surgery compensatory behaviours demonstrate innovative adaptation of the aryepiglottic sphincter mechanism to generate ‘substitution voice’. Numerous videos/audio of clinical cases illustrate the effect of pathologies on voice quality. Pre- and post-operative speech production show how altered structures create altered voice quality. Epilaryngeal tube control is shown to be the cornerstone of our ability to adapt. Mongolian long song and human beatboxing illustrate the use of the professional voice. Clinicians as well as linguists will benefit from the detailed new exploration of the laryngeal articulator and its adaptability.

Chapter 6 investigates the earliest steps of how infants acquire the phonetic capacity to speak. It is relevant to voice quality that infants begin life with laryngeally constricted qualities, based on which they develop elaborated oral articulations with laryngeal quality as background. Ontogenetically, speech begins with the laryngeal articulator. New drawings illustrate the infant vocal tract (vs. the adult vocal tract). The companion website contains over 100 audio files of phonetic stages during the first year of life, comparing articulatory development in English with Tibeto-Burman Bái. The LAM provides the basis for understanding the distribution of non-syllabic and syllabic utterances, focusing on intermediate ‘mixed’ utterances. During the first several months of life, infants parse phonetic possibilities, refining the identity of potential individual sounds against the emerging backgrounds of long-term laryngeal qualities. Laryngeal voice quality reflects a complex interaction between the developing physiology of the infant vocal tract and the innate disposition to engage in vocal exploration, playing a crucial role in speech development.

Terminology for voice quality is revised, particularly for the lower vocal tract. The concepts of ‘voice quality’ as the long-term, habitual postural settings in an accent and ‘voice quality’ as the vibratory, phonatory portion of speech are reconciled through the laryngeal articulator mechanism that explains how multiple configurational adjustments and vibratory elements are achieved in the lower vocal tract. The origins of voice quality theory are reviewed, and articulatory settings of the laryngeal mechanism, velopharyngeal opening, the tongue, the jaw, and the lips are reviewed. The descriptions from Laver (1980) are reinforced, connections to laryngeal articulation are made explicit, and the musculature responsible for each setting is outlined. New drawings of the mechanisms of the vocal tract provide a fresh perspective on articulatory movements and resulting auditory qualities. Pharyngeal/epiglottal articulations are remapped, and their status as laryngeal configurations is made explicit.

Instrumental phonetic techniques illustrate the analyses behind the interpretation of laryngeal articulator function and laryngeal sounds. High-speed laryngoscopy demonstrates aryepiglottic trilling. Cineradiography demonstrates where and how epiglottal stop and voiceless and voiced aryepiglottic trilling are generated. Simultaneous laryngoscopy and laryngeal ultrasound gauge the vertical displacement of the larynx during laryngeally constricted articulations compared to opening manoeuvres. MRI provides insight into the effects of lower-vocal-tract configurations on changes in vowel quality. Computational modelling shows how algorithms that account for voicing can be adapted to explain the mechanics of complex laryngeal vibrations. Vocal-ventricular fold coupling (VVFC) occurs as a vertical compression effect in stopping airflow and in constricted phonation types (creaky voice, harsh voice) and is modelled to illustrate the relationships and actions among laryngeal structures. Analyses, data capture, explanations of the algorithms, and videos of the working models are incorporated in the online companion materials, including articulatory simulations by the laryngeal component of the ‘ArtiSynth’ model.

Chapter 5 explores the implications of the Laryngeal Articulator Model for phonology and the place of voice quality in phonological analysis. The Phonological Potentials Model (PPM) is explained, and synergistic and anti-synergistic relations are mapped in diagrams. Earlier phonological approaches that do not consider the laryngeal articulator are reviewed, while the PPM demonstrates how cooperative lingual-laryngeal activity can be accommodated in phonological analysis. Case studies of languages having lower-vocal-tract contrasts (vocal register, pharyngealization in click languages) give an idea of the network of articulatory relationships that form the grounding of phonological representations. We highlight vocalic-harmony (so-called [ATR]), syllabic, and tense–lax registers in West African, Northeast African and Southeast Asian languages. The case of Southern Wakashan pharyngeal genesis illustrates the role of voice quality in sound change.

Recapitulates the phonetic theories of Abercrombie and Laver, introduces the Laryngeal Articulator Model of the vocal tract, and refers to the iPA Phonetics app as a tool for accessing auditory samples of voice qualities and visual images of articulations. The model supersedes the simple glottal-phonation paradigm of the larynx, replacing it with the ‘two-part vocal tract,’ containing a complex articulator in the lower vocal tract paralleling the tongue in the oral vocal tract.

Laryngeal voice quality classifications and ‘states of the larynx’ are reviewed and expanded. Supplementary notes accompanying the text describe the video, audio, and text materials in the online companion site that accompanies the book to illustrate and explain the articulatory production of each laryngeal voice quality. Constricted phonation types exploit degrees of laryngeal articulator tightening with concomitant lingual and larynx-height settings. A new continuum of laryngeal stricture, from open to closed, is introduced. Glottal, ventricular, and epiglottal stop are illustrated. Breathiness vs. whisperiness is redefined. Creaky voice and varieties of harsh voice are investigated, including ventricular production and trilling of the aryepiglottic folds. New drawings and laryngoscopic photographs capture the extent of open and constricted postures. Breathy states with and without voicing are compared side by side with whispery states. The concept of vocal tract tension is reattributed to constrictive settings of the laryngeal articulator mechanism. The aim is to paint an auditory portrait of the articulatory configurations of the vocal tract.

Chapter 8 summarizes the ramifications of the Laryngeal Articular Model for the phonetic description of voice quality and investigates its place in phonetic theory. Predispositions for background voice qualities to underlie different vowel qualities are identified. It is argued that there is a parallel between the coarticulatory path that infants follow in their earliest speech development and elements in the process of phonetic sound change. The laryngeal articulator as an enabler of sound change is explored. Theories of ontogenetic speech development are reviewed (concepts of ‘speechlikeness,’ autogeneration, frame/content, cyclicity, reduplication, variegation) and reinterpreted to reflect the scope of laryngeal behaviour outlined in this volume. The discussion evaluates the implications of the revised view of laryngeal phonetic behaviour for the phylogeny of human speech. The physiology of the larynx is shown to permit a wider range of speech production than formerly assumed and to accommodate, on phonetic grounds, an earlier time period for the appearance of speech in human ancestors, as hypothesized in recent anthropological and genetic research.