Pitch contour
Encyclopedia
In linguistics
, speech synthesis
, and music
, the pitch contour of a sound is a function or curve that tracks the perceived pitch
of the sound over time.
Pitch contour may include multiple sounds utilizing many pitches, and can relate to frequency function at one point in time to the frequency function at a later point.
It is fundamental to the linguistic concept of tone
, where the pitch or change in pitch of a speech unit over time affects the semantic meaning of a sound. It also indicates intonation
in pitch accent
languages.
One of the primary challenges in speech synthesis
technology, particularly for Western languages, is to create a natural-sounding pitch contour for the utterance as a whole. Unnatural pitch contours result in synthesis that sounds "lifeless" or "emotionless" to human listeners, a feature that has become a stereotype of speech synthesis in popular culture.
In music
, the pitch contour focuses on the relative change in pitch over time of a primary sequence of played notes. The same contour can be transposed without losing its essential relative qualities, such as sudden changes in pitch or a pitch that rises or falls over time.
Pure tone
s have a clear pitch, but complex sounds such as speech and music typically have intense peaks at many different frequencies. Nevertheless, by establishing a fixed reference point in the frequency function of a complex sound, and then observing the movement of this reference point as the function translates, one can generate a meaningful pitch contour consistent with human experience.
For example, the vowel
e has two primary formant
s, one peaking between 400 and 600 Hz and one between 2200 and 2600 Hz. When a person speaks a sentence involving multiple e sounds, the peaks will shift within these ranges, and the movement of the peaks between two instances establishes the difference in their values on the pitch contour.
Linguistics
Linguistics is the scientific study of human language. Linguistics can be broadly broken into three categories or subfields of study: language form, language meaning, and language in context....
, speech synthesis
Speech synthesis
Speech synthesis is the artificial production of human speech. A computer system used for this purpose is called a speech synthesizer, and can be implemented in software or hardware...
, and music
Music
Music is an art form whose medium is sound and silence. Its common elements are pitch , rhythm , dynamics, and the sonic qualities of timbre and texture...
, the pitch contour of a sound is a function or curve that tracks the perceived pitch
Pitch (music)
Pitch is an auditory perceptual property that allows the ordering of sounds on a frequency-related scale.Pitches are compared as "higher" and "lower" in the sense associated with musical melodies,...
of the sound over time.
Pitch contour may include multiple sounds utilizing many pitches, and can relate to frequency function at one point in time to the frequency function at a later point.
It is fundamental to the linguistic concept of tone
Tone (linguistics)
Tone is the use of pitch in language to distinguish lexical or grammatical meaning—that is, to distinguish or inflect words. All verbal languages use pitch to express emotional and other paralinguistic information, and to convey emphasis, contrast, and other such features in what is called...
, where the pitch or change in pitch of a speech unit over time affects the semantic meaning of a sound. It also indicates intonation
Intonation (linguistics)
In linguistics, intonation is variation of pitch while speaking which is not used to distinguish words. It contrasts with tone, in which pitch variation does distinguish words. Intonation, rhythm, and stress are the three main elements of linguistic prosody...
in pitch accent
Pitch accent
Pitch accent is a linguistic term of convenience for a variety of restricted tone systems that use variations in pitch to give prominence to a syllable or mora within a word. The placement of this tone or the way it is realized can give different meanings to otherwise similar words...
languages.
One of the primary challenges in speech synthesis
Speech synthesis
Speech synthesis is the artificial production of human speech. A computer system used for this purpose is called a speech synthesizer, and can be implemented in software or hardware...
technology, particularly for Western languages, is to create a natural-sounding pitch contour for the utterance as a whole. Unnatural pitch contours result in synthesis that sounds "lifeless" or "emotionless" to human listeners, a feature that has become a stereotype of speech synthesis in popular culture.
In music
Music
Music is an art form whose medium is sound and silence. Its common elements are pitch , rhythm , dynamics, and the sonic qualities of timbre and texture...
, the pitch contour focuses on the relative change in pitch over time of a primary sequence of played notes. The same contour can be transposed without losing its essential relative qualities, such as sudden changes in pitch or a pitch that rises or falls over time.
Pure tone
Pure tone
A pure tone is a tone with a sinusoidal waveshape.A sine wave is characterized by its frequency, the number of cycles per second—or its wavelength, the distance the waveform travels through its medium within a period—and the amplitude, the size of each cycle...
s have a clear pitch, but complex sounds such as speech and music typically have intense peaks at many different frequencies. Nevertheless, by establishing a fixed reference point in the frequency function of a complex sound, and then observing the movement of this reference point as the function translates, one can generate a meaningful pitch contour consistent with human experience.
For example, the vowel
Vowel
In phonetics, a vowel is a sound in spoken language, such as English ah! or oh! , pronounced with an open vocal tract so that there is no build-up of air pressure at any point above the glottis. This contrasts with consonants, such as English sh! , where there is a constriction or closure at some...
e has two primary formant
Formant
Formants are defined by Gunnar Fant as 'the spectral peaks of the sound spectrum |P|' of the voice. In speech science and phonetics, formant is also used to mean an acoustic resonance of the human vocal tract...
s, one peaking between 400 and 600 Hz and one between 2200 and 2600 Hz. When a person speaks a sentence involving multiple e sounds, the peaks will shift within these ranges, and the movement of the peaks between two instances establishes the difference in their values on the pitch contour.
Music bibliography
- Cogan and Escot (1976). Sonic Design: The Nature of Sound and Music. (Englewood Cliffs, NJ: Prentice-Hall.
- Friedmann, "A Methodology for the Discussion of Contour: Its Application to Schoenberg's Music," Journal of Music Theory 29 (1985): 223-48.
- Morris, Composition with Pitch-Classes: A Theory of Compositional Design (New Haven and London: Yale University Press, 1987)
- Polansky, "Morphological Metrics: An Introduction to a Theory of Formal Distances" in Proceedings of the International Computer Music Conference (San Francisco: Computer Music Association, 1987).
- Larry Polansky; Richard Bassein (1992). "Possible and Impossible Melody: Some Formal Aspects of Contour", Journal of Music Theory, Vol. 36, No. 2. (Autumn, 1992), pp. 259–284.
Ethnomusicology
- Mieczyslaw Kolinski, "The Structure of Melodic Movement: A New Method of Analysis," Studies in Ethnomusicology 2 (1965): 96-120
- Charles R. Adams, "Melodic Contour Typology," Ethnomusicology 20 (1976): 179- 215.
- Charles Seeger, "On the Moods of a Music-Logic." Journal of the American Musicology Society 8 (1960): 224-61.
- Elizabeth West Marvin, "A Generalization of Contour Theory to Diverse Musical Spaces: Analytical Applications to the Music of Dallapiccola and Stockhausen" in Musical Pluralism: Aspects of Aesthetics and Structure Since 1945 (forthcoming). Contains review of these and earlier articles.
External links
- Reuven Tsur. Phonetic Cues and Dramatic Function Artistic Recitation of Metered Speech. Tel Aviv University. A research article containing images illustrating many specific examples of pitch contours for recited poetry.