Cardinal vowels
Cardinal vowels are a standardized set of reference vowel sounds in phonetics, developed by British phonetician Daniel Jones to provide fixed points for accurately describing and comparing the quality of vowels across languages.[1] The system comprises 18 cardinal vowels, including eight primary ones that occupy the peripheral positions in the vowel space—defined by extreme tongue heights (high to low) and positions (front to back)—along with eight secondary vowels that reverse the typical lip-rounding patterns and two additional centralized vowels.[2] These vowels, which rarely occur naturally in speech, form the basis of the International Phonetic Alphabet's vowel chart and enable precise transcription by anchoring other vowel sounds relative to them.[3] Jones introduced the cardinal vowel system in his 1917 English Pronouncing Dictionary and elaborated it in An Outline of English Phonetics (1918), drawing from X-ray imaging and auditory analysis to define articulatory positions.[1] The primary cardinals (numbered 1 to 8) feature unrounded lips for front vowels (e.g., as CV1, the highest front unrounded) and rounded lips for back vowels (e.g., as CV8, the highest back rounded), while secondary cardinals (9 to 16) invert this rounding for finer distinctions.[3] Jones recorded demonstrations of these vowels in 1917, 1943, and 1956, which remain influential resources for phonetic training and remain relevant in modern linguistics for mapping vowel inventories.[2] This framework revolutionized phonetic description by establishing a universal scale, independent of any single language, and continues to underpin vowel analysis in fields like dialectology and language teaching.[1]History and Development
Origins with Daniel Jones
Daniel Jones, a prominent British phonetician, developed the cardinal vowel system during the early 20th century while working at University College London (UCL), where he was appointed as a part-time lecturer in phonetics in 1907 and later became head of the Department of Phonetics in 1912.[4][5] His work was heavily influenced by his studies under Paul Passy in Paris around 1905–1906, which exposed him to the principles of phonetic transcription and the need for standardized vowel references within the emerging International Phonetic Alphabet (IPA).[6] As a key member of the International Phonetic Association—joining in 1906 and serving as editor of its journal Le Maître Phonétique—Jones sought to address inconsistencies in vowel description across languages, drawing on collaborative discussions with Passy and other phoneticians to establish a universal framework.[5][6] The cardinal vowel system originated as a response to the limitations of using language-specific examples, such as those from English or French, for phonetic transcription, which often led to variable interpretations in IPA usage.[1] By 1917, Jones had formulated a set of eight primary cardinal vowels as fixed auditory and articulatory reference points, designed to map the extremes of the vowel space without reliance on any particular language's phonology, thereby providing reliable anchors for cross-linguistic comparisons.[4][6] This approach emphasized perceptual uniformity, ensuring that phoneticians could approximate vowel qualities consistently regardless of their native language backgrounds.[6] To demonstrate the system, Jones recorded the primary cardinal vowels using his own voice as the model, producing gramophone discs for His Master's Voice (HMV) in 1917, which served as the first auditory exemplars for teaching and research.[4] These recordings were pivotal in disseminating the system, with later re-recordings in 1943 and 1956 to account for age-related vocal changes.[7] Jones detailed the cardinal vowels in his seminal publication An Outline of English Phonetics (first edition, 1918), where he outlined their positions and purposes, building on his earlier experimental work and collaborations within the International Phonetic Association.[6]Standardization and Evolution
The cardinal vowel system, initially developed by Daniel Jones, gained formal recognition through its integration into the International Phonetic Association (IPA) framework during the mid-20th century, with key advancements occurring in the 1940s. The IPA's 1947 chart revision incorporated modifications to vowel symbols, such as the introduction of lowered variants like ɩ for near-high front unrounded and ɷ for near-high back rounded, enhancing the precision of the vowel trapezium diagram that references cardinal positions.[8] This built on earlier efforts, leading to the 1949 publication of The Principles of the International Phonetic Association, which formalized the vowel quadrilateral as a standard tool for phonetic description, embedding cardinal vowels as reference points within IPA notation.[9] Further refinements came at the 1989 Kiel Convention, where the IPA revised its overall chart and principles, adjusting the vowel space representation to better align with articulatory and acoustic data while retaining the cardinal framework as a foundational element.[10] Subsequent contributions from phoneticians like Peter Ladefoged helped evolve the system's practical application and documentation. In the 1970s, Ladefoged produced recordings of the cardinal vowels, drawing on demonstrations by former students of Jones to incorporate a broader range of speaker diversity and reflect variations in production across accents.[11] These efforts, featured in his 1975 textbook A Course in Phonetics, emphasized auditory training and provided updated audio exemplars that deviated slightly from Jones's originals to account for natural phonetic variability.[12] Such recordings facilitated greater accessibility for teaching and research, bridging traditional articulatory standards with emerging empirical studies. The evolution of recording technology paralleled these institutional developments, transitioning from mechanical to electrical and eventually digital formats. Jones's initial 1917 gramophone recordings used acoustic horns and diaphragms, capturing limited frequency ranges without amplification.[13] By 1956, Jones re-recorded the cardinal vowels on electrical disc for Linguaphone, enabling clearer audio fidelity and allowing comparisons that highlighted consistency in his productions despite age.[14] Later, Ladefoged's 1970s analog tapes and subsequent digital remasterings extended this progression, supporting modern analyses like formant extraction and ensuring the cardinal system's enduring utility in phonetic education.[11]Definition and Principles
Core Concept of Cardinal Vowels
Cardinal vowels constitute a standardized reference system in phonetics, consisting of 8 primary, 8 secondary, and 2 centralized vowels that function as perceptual anchors along a continuum of tongue height (from close to open) and backness (from front to back). These vowels are not tied to any specific language but serve as fixed points for objectively describing vowel qualities worldwide. The primary set includes unrounded front vowels and rounded back vowels at extreme positions, while the secondary set introduces variations in lip rounding to cover additional perceptual contrasts.[1] The core purpose of cardinal vowels is to enable precise, language-neutral comparisons of any vowel sound by relating it to these anchors, for example, characterizing a given vowel as "slightly lower and more back than Cardinal Vowel 2" or "more open than Cardinal Vowel 1." This approach allows phoneticians to transcribe and analyze vowels consistently without relying on subjective or language-specific descriptions, facilitating cross-linguistic research and phonetic education. By providing a shared framework, cardinal vowels ensure that descriptions remain verifiable through auditory training rather than varying interpretations.[15] A fundamental principle underlying the cardinal vowel system is auditory equidistance, where the perceptual intervals between consecutive vowels are designed to sound equally spaced to the trained ear, emphasizing auditory perception over rigid articulatory or physiological metrics. This spacing creates a balanced perceptual scale, though it is arbitrary and learned through rote practice rather than derived from uniform physical steps. The positions were systematized to map the perceptual boundaries of the vowel space effectively.[1][15] The cardinal vowels form the foundational structure for the International Phonetic Alphabet (IPA) vowel chart, which adopts their arrangement of height and backness but extends it with supplementary symbols for intermediate or centralized vowels not captured by the cardinal set alone. While the IPA symbols approximate cardinal qualities, they are not identical, as the chart accommodates a broader range of attested sounds across languages. This integration underscores the cardinal system's role as a perceptual standard within the IPA framework.[1]Articulatory and Auditory Foundations
The articulatory basis of cardinal vowels lies in the physiological configuration of the vocal tract, primarily involving the tongue's position along two dimensions: height, ranging from close (high) to open (low), and backness, from front to central to back. Lip rounding and jaw opening further modulate the resonance, with cardinal vowels positioned at the extremes of these parameters to serve as reference points. For instance, the tongue is raised as high and forward as possible for the front-close vowel without producing friction, while the open-back vowel involves the lowest and most retracted tongue position achievable. These configurations are not arbitrary but reflect the functional limits of tongue mobility within the oral cavity.[1][16] The auditory foundation of the cardinal vowel system relies on the perceptual capabilities of trained phoneticians, who recognize these vowels as forming equidistant steps in vowel quality across the perceptual space. This equidistance is subjective and learned, based on consistent differences in auditory timbre rather than precise measurements, allowing for reliable comparisons of vowel sounds in different languages. While underlying formant frequencies contribute to these perceptual distinctions, the system emphasizes auditory judgment over acoustic quantification.[15][16] Phoneticians acquire proficiency in producing and recognizing cardinal vowels through structured training, typically involving imitation of standardized reference recordings over several weeks of ear-training and articulatory practice. This process includes listening to isolated vowel tokens and nonsense words, followed by replication to internalize the extreme positions and perceptual intervals. Such training enables consistent replication without deviating into adjacent vowel qualities.[17][18] Physiologically, the cardinal vowels represent the vocal tract's capacity to attain these extreme articulatory targets without strain or compensatory adjustments that could alter the intended quality, such as excessive tension or friction noise. The tongue's range of motion is constrained by the jaw, pharynx, and oral cavity dimensions, ensuring that the reference positions are natural maxima rather than forced exaggerations. This alignment with human anatomical limits underpins the system's practicality for phonetic description.[1][16]The Cardinal Vowel Set
Primary Cardinal Vowels
The primary cardinal vowels comprise eight standardized reference sounds central to Daniel Jones's system for phonetic description, established in his 1917 work The English Pronouncing Dictionary and elaborated in An Outline of English Phonetics (1918). These vowels define the peripheral boundaries of the human vocal tract's vowel-producing capacity, serving as immutable auditory anchors that phoneticians learn through repeated listening to recordings, such as those produced by Jones himself. Unlike vowels in specific languages, they are idealized qualities not tied to any natural occurrence but designed for consistent cross-linguistic comparison and transcription. Their positions are plotted on the IPA vowel trapezium—a quadrilateral diagram with tongue height on the vertical axis (close at the top, open at the bottom) and tongue advancement on the horizontal axis (front on the left, back on the right)—forming the foundational points along the front unrounded and back rounded edges.[19] The following table summarizes the eight primary cardinal vowels, including their numbering, IPA symbols, articulatory configurations (tongue position and height, lip posture, jaw opening), and roles as auditory references. Articulatory details are based on Jones's specifications, emphasizing extreme yet stable positions to avoid consonantal friction.[1]| Number | Symbol | Articulatory Position | Auditory Reference Quality |
|---|---|---|---|
| CV1 | (close front unrounded) | Tongue arched maximally high and forward toward the hard palate; lips spread horizontally; jaw minimally open or closed. | Highest and frontmost unrounded vowel, serving as the upper limit for front vowel height without producing a fricative sound.[3] |
| CV2 | (close-mid front unrounded) | Tongue raised to close-mid height in the front, slightly lower than CV1; lips spread; jaw moderately open. | Intermediate between CV1 and CV3, marking the boundary where front vowels begin to perceptibly lower in height.[3] |
| CV3 | [ɛ] (open-mid front unrounded) | Tongue positioned at open-mid height in the front, with the front lowered noticeably; lips spread or neutral; jaw openly dropped. | Halfway between CV2 and CV4, providing a reference for mid-level front unrounded vowels.[3] |
| CV4 | (open front unrounded) | Tongue lowered as far as possible in the front without bunching; lips spread; jaw maximally open to its physiological limit. | Lowest front unrounded vowel, acting as the neutral open reference point for calibrating all other open vowels.[1] |
| CV5 | [ɑ] (open back unrounded) | Tongue flattened low and retracted toward the soft palate; lips neutral or slightly spread; jaw maximally open. | Lowest back unrounded vowel, contrasting with CV4 to define the horizontal spread of open vowel space.[1] |
| CV6 | [ɒ] (open back rounded) | Tongue low and back, similar to CV5 but with slight centralization; lips firmly rounded and protruded; jaw widely open. | Open back rounded counterpart to CV5, establishing the starting point for rounded back vowels at maximal openness.[19] |
| CV7 | (close-mid back rounded) | Tongue raised to close-mid height in the back; lips rounded and protruding; jaw moderately open. | Intermediate between CV6 and CV8, referencing the close-mid level for back rounded vowels.[19] |
| CV8 | (close back rounded) | Tongue raised maximally high and back toward the soft palate; lips rounded and protruding; jaw closed or minimally open. | Highest back rounded vowel in the primary set, delineating the upper limit for back rounded qualities.[19] |
Secondary Cardinal Vowels
The secondary cardinal vowels were later introduced by Daniel Jones to supplement the primary set, addressing the need for reference points that better cover rounded front vowel qualities and unrounded back vowel qualities not adequately represented in the original eight primaries.[1] These eight vowels reverse the lip-rounding of the primaries and are defined as follows:- CV9: , the close front rounded vowel, produced with the tongue in a high front position like CV1 and protruded lips.
- CV10: [ø], the close-mid front rounded vowel, with the tongue raised to a close-mid front position like CV2 and lip rounding.
- CV11: [œ], the open-mid front rounded vowel, featuring an open-mid front tongue position like CV3 combined with lip protrusion.
- CV12: [ɶ], the open front rounded vowel, with the tongue low front like CV4 and rounded lips.
- CV13: [ɯ], the close back unrounded vowel, articulated with a high back tongue position like CV8 but spread lips.
- CV14: [ɤ], the close-mid back unrounded vowel, with close-mid back tongue like CV7 and unrounded lips.
- CV15: [ʌ], the open-mid back unrounded vowel, with open-mid back tongue position and neutral lips.
- CV16: [ɑ], the open back unrounded vowel, reinforcing the primary CV5 but as unrounded counterpart to back rounded positions.[1][19]
Centralized Cardinal Vowels
The cardinal vowel set is completed by two additional centralized vowels, serving as references for central positions in the vowel space:- CV17: [ɨ], the close central unrounded vowel, with the tongue raised high and central, lips neutral.
- CV18: [ə], the mid central vowel (schwa), with the tongue at mid height and central, lips neutral.