|Applied and experimental|
Phonetics (pronounced //, from the Greek: φωνή, phōnē, 'sound, voice') is a branch of linguistics that comprises the study of the sounds of human speech, or—in the case of sign languages—the equivalent aspects of sign. It is concerned with the physical properties of speech sounds or signs (phones): their physiological production, acoustic properties, auditory perception, and neurophysiological status. Phonology, on the other hand, is concerned with the abstract, grammatical characterization of systems of sounds or signs.
The field of phonetics is a multilayered subject of linguistics that focuses on speech. In the case of oral languages there are three basic areas of study:
These areas are inter-connected through the common mechanism of sound, such as wavelength (pitch), amplitude, and harmonics.
Phonetics was studied as early as the 4th century BC in the Indian subcontinent, with Pāṇini's account of the place and manner of articulation of consonants in his treatise on Sanskrit. The major Indic alphabets today order their consonants according to Pāṇini's classification. The Phoenicians are credited as the first to create a phonetic writing system, from which all major modern phonetic alphabets are now derived.
Modern phonetics begins with attempts—such as those of Joshua Steele (in Prosodia Rationalis, 1779) and Alexander Melville Bell (in Visible Speech, 1867)—to introduce systems of precise notation for speech sounds.
The International Phonetic Alphabet (IPA) is used as the basis for the phonetic transcription of speech. It is based on the Latin alphabet and is able to transcribe most features of speech such as consonants, vowels, and suprasegmental features. Every documented phoneme available within the known languages in the world is assigned its own corresponding symbol.
Phonology concerns itself with systems of phonemes, abstract cognitive units of speech sound or sign which distinguish the words of a language. Phonetics, on the other hand, concerns itself with the production, transmission, and perception of the physical phenomena which are abstracted in the mind to constitute these speech sounds or signs.
Using an Edison phonograph, Ludimar Hermann investigated the spectral properties of vowels and consonants. It was in these papers that the term formant was first introduced. Hermann also played vowel recordings made with the Edison phonograph at different speeds in order to test Willis' and Wheatstone's theories of vowel production.
In contrast to phonetics, phonology is the study of how sounds and gestures pattern in and across languages, relating such concerns with other levels and aspects of language. Phonetics deals with the articulatory and acoustic properties of speech sounds, how they are produced, and how they are perceived. As part of this investigation, phoneticians may concern themselves with the physical properties of meaningful sound contrasts or the social meaning encoded in the speech signal (socio-phonetics) (e.g. gender, sexuality, ethnicity, etc.). However, a substantial portion of research in phonetics is not concerned with the meaningful elements in the speech signal.
While it is widely agreed that phonology is grounded in phonetics, phonology is a distinct branch of linguistics, concerned with sounds and gestures as abstract units (e.g., distinctive features, phonemes, mora, syllables, etc.) and their conditioned variation (via, e.g., allophonic rules, constraints, or derivational rules). Phonology relates to phonetics via the set of distinctive features, which map the abstract representations of speech units to articulatory gestures, acoustic signals, and/or perceptual representations.
Phonetics as a research discipline has three main branches:
Phonetic transcription is a system for transcribing sounds that occur in a language, whether oral or sign. The most widely known system of phonetic transcription, the International Phonetic Alphabet (IPA), provides a standardized set of symbols for oral phones. The standardized nature of the IPA enables its users to transcribe accurately and consistently the phones of different languages, dialects, and idiolects. The IPA is a useful tool not only for the study of phonetics, but also for language teaching, professional acting, and speech pathology.
Applications of phonetics include: