Original post in Spanish. Translated by artificial intelligence to achieve a wider diffusion. Please, if you notice errors, contact us in English or Spanish. Thank you for your understanding.

Of the four perceptual qualities of sound – intensity, pitch, timbre and duration – timbre is the most controversial. According to the RAE (Royal Academy of the Spanish Language), timbre is the “quality of sound determined by the effect it produces on the listener”. However, the Acoustical Society of America uses the definition of Helmholz (1954) and states that timbre is indeed a perceptual characteristic that allows two sounds to be distinguished, but it is necessary for both sounds to have the same intensity and fundamental frequency. Here you can also find several definitions of timbre by different authors.

The main problem with timbre, as a perceptual quality, is that it has no objective quantity with which to measure it, whereas for tone we can measure frequency in Hertz, for intensity we can measure amplitude in decibels and duration in seconds. As well as being a controversial quality, the concept of timbre itself is questioned in the literature.

Most authors consider the terms timbre and voice quality to be synonymous. Sapir (1927) or Drake (1937) were some of the first, and they were followed by many others such as Laver (1975), Dejonckere and co-workers (2001), Kreiman, Sidtis and Gerrat (2008), Hewlett and Beck (2013), etc. Scherer et al. (2013) explain that the term voice quality refers to what is perceived as timbre or voice colour. However, since timbre can refer to any sound, the term quality is often preferred when talking about voice. In this sense, Crystal (1976) considers timbre to be different from voice quality. For this author, the term timbre refers to the resonances of any sound, whereas voice quality can only be talked about when the difference produces linguistic contrasts.

The term quality is also controversial. Sundberg (2013) distinguishes between vowel quality, which is found in the lower formants of the spectrum, and voicing quality, which depends on the higher formants.

Formant: Zone of the frequency scale in which a sound has a higher concentration of energy. It can also be defined as each of the resonances of the vocal tract (Gil, 1988) (Image from: CC BY 2.0).

But even the term voice quality is controversial. In a broad sense, since most authors consider timbre and voice quality to be synonymous, it could be said that the characteristics we perceive that help us to distinguish one voice from another are due to several factors. Firstly, the anatomical structure of the speaker; secondly, the adjustments the speaker makes with the laryngeal muscles; and thirdly, the articulatory adjustments made by the supraglottic structures, i.e. the articulatory system.

Glottic and laryngeal structures. Images by Henry Vandyke Carter [Public domain], via Wikimedia Commons

 

 

Honikman (1964), Laver (1968, 1980) and Esling (1983), among others, believe that the quality of the voice is derived from the way in which all these structures are assembled and coordinated. Other authors, however, believe that it is necessary to distinguish between the sound produced by the glottal source and the sound produced by the action of all the supralaryngeal articulatory structures. And the quality of the voice begins to be distinguished from the modes of phonation. However, we will leave this complex subject for a second entry.

For more information…

• Crystal, D. (1976): Prosodic systems and intonation in English, (Vol. 1), Cambridge University Press Archive.
• Dejonckere, P. H.; Bradley, P.; Clemente, P.; Cornut, G.; Crevier-Buchman, L.; Friedrich, G. y Woisard, V. (2001). “A basic protocol for functional assessment of voice pathology, especially for investigating the efficacy of (phonosurgical) treatments and evaluating new assessment techniques”, European Archives of Oto-rhino-laryngology, 258(2), pp. 77-82.
• Drake, O. J. (1937): “Toward an improved vocal quality”, Quarterly Journal of Speech, 23(4), pp. 620-626.
• Esling, J. H. (1983): «A laryngographic investigation of phonation type and laryngeal configurations», Working Papers of the Linguistics Circle, 3 (1), pp. 14-36.
• Gil Fernández, J. (1988): Los sonidos del lenguaje, Madrid, Síntesis.
• Helmholtz, H. von (1954): On the sensations of tone as a physiological basis for the theory of
  music, A.J.Ellis (ed. y trad.), New York, Dover, (Publicado originalmente en 1863).
• Honikman, B. (1964): «Articulatory settings» en D. Abercrombie, D. B. Fry, P. A. D. MacCarthy, N. C. Scott y J. L. L. Trim (eds.) In honor of Daniel Jones, Londres, Longmans, pp. 73-84.
• Kreiman, J.; Vanlancker-Sidtis, D. y Gerrat, B. R. (2008). «Perception of voice quality» en D. B. Pisoni y R. E. Remez (eds.), Handbook of speech perception, Blackwell, pp. 338-362.
• Laver, J. (1968): Voice quality and indexical information. International Journal of Language & Communication Disorders, 3, 1, pp. 43-54.
• Laver, J. (1975): «Individual features in voice quality», Ph.D. dissertation, University of Edinburgh.
• Laver, J. (1980): The Phonetic Description of Voice Quality, Cambridge, Cambridge University Press.
• Sapir, E. (1927): «Speech as a Personality Trait», American Journal of Sociology, pp. 892-905.
• Scherer, S.; Kane, J.; Gobl, C. y Schwenker, F. (2013). «Investigating fuzzy-input fuzzy-output support vector machines for robust voice quality classification», Computer Speech & Language, 27(1), 263-287.
• Sundberg, J. (2013). «The perception of singing» en D. Deutsch (ed.), The psychology of music, Elsevier, pp. 59-98.

Published by Pilar Lirio, September 2023.