Speech Production: Places of Articulation and Voicing

Voicing, phonation, and how we tell when vocal folds vibrate

• Vocal folds can be open and air flows freely, producing voiceless sounds like S (unvoiced) versus Z (voiced) where the folds vibrate.
• Simple test: place a hand on the throat and alternate between saying S and Z. S → no perceived vibration; Z → you can feel vibration as the vocal folds open and close rapidly.
• Voicing or phonation refers to whether the vocal folds are vibrating during sound production.
• Fundamental frequency: describes how quickly the vocal folds vibrate; commonly associated with perceived pitch.
  • Symbol sometimes used: $F_0$.
  • People who speak with a high-pitched voice have a high $F<em>0$; those with a low-pitched voice have a low $F</em>0$.
• Also mentioned: F0 is sometimes referred to as the first formant? (Note: in this transcript, F0 is the term for fundamental frequency.)
• Practical tip: practice alternating S and Z to feel the difference in voicing; whispering involves no vocal fold vibration.

Whispering and supralaryngeal articulation

• Speaking style with no vocal fold vibration: whispering. Verify by whispering with a hand on the throat to feel the absence of vibration.
• Main articulation above the larynx is termed supralaryngeal (supra = above; laryngeal = larynx).
• There are three main cavities involved in speech sounds:
  • Pharynx (the space behind the tongue and above the larynx)
  • Oral cavity (the mouth)
  • Nasal cavity (inside the nose)
• The act of producing sounds is called articulation, i.e., how articulators join or come close together.
• Articulators can be categorized as:
  • Passive articulators: stationary structures (typically the ones on the top part of the mouth) — include teeth, alveolar ridge, hard palate, soft palate (velum), etc.
  • Active articulators: movable parts (e.g., lips, tongue) that move toward passive articulators.

Key anatomical landmarks inside the vocal tract

• Passive articulators (top part of the mouth):
  • Nose (external boundary)
  • Lip
  • Teeth
  • Alveolar ridge (ridge behind the teeth; behind-the-teeth ledge)
  • Hard palate (the dome-like roof of the mouth)
  • Soft palate / Velum (the soft tissue towards the back of the mouth; separates oral from nasal cavity when raised)
• Velum (soft palate) and the nasal/oral split:
  • Velum can be lowered to allow air into the nasal cavity (nasal sounds).
  • Velum can be raised to block the nasal cavity (oral sounds).
  • Uvula is the little dangly part at the end of the velum.
• Active articulators (movable parts):
  • Lips (can move for rounding or closure)
  • Tongue (highly versatile; several sub-parts)
  • Tip of the tongue (front-most part)
  • Blade (just behind the tip)
  • Front of the tongue
  • Back of the tongue
  • Tongue root
  • Lingual sounds: sounds produced with the tongue (most sounds involve the tongue in some way)
• In trying to locate which part of the tongue is used, an exercise: inhale while saying “s” and then “sh” to feel the different tongue positions before voicing.

Place of articulation (front to back)

• General idea: sounds are named by where the articulators come together or come close in the mouth.
• Important note: there are both passive and active articulators; the active part moves toward the passive stationary part.
• Start at the front and move back:
  • Bilabial: two lips coming together (active lips with passive upper teeth). English examples: p (puh), b (buh), m, and also w (lip rounding; bilabial). A quick note: sometimes see R with lip rounding as a related variation.
  • Labiodental: lower lip and upper teeth coming together. English examples: f, v.
  • Dental / Interdental: either interdental (American English) with tongue tip protruding between teeth, or dental (British English) with tongue resting behind the teeth.
  • Example: interdental θ (as in theta) and ð (as in they) in many American speakers; British often dentalized.
  • Alveolar: sounds produced with the tongue tip or blade near the alveolar ridge (ridge behind the teeth).
  • Examples: t, d (stops), s, z (fricatives), n (nasal), l (lateral).
  • Important notes: tongue-tip up vs tongue-tip down variation for /s/ and /z/; this is a common individual difference.
  • The alveolar lateral /l/: air flows over the sides of the tongue (lateral sound).
  • Post-alveolar: sounds just behind the alveolar ridge (not fully on the palate). Often includes sounds like /ʃ/ (sh), /ʒ/ (zh), /tʃ/ (ch), /dʒ/ (j).
  • In English, these can be enriched by lip rounding to make the sounds more distinct from alveolars.
  • Retroflex: raised and curled tongue tip; common discussion around English R; variation exists within and across speakers (some use bunched R vs retroflex R).
  • Palatal: high front place; English example is the /j/ sound as in “yes.”
  • Velar: back of tongue toward the velum; English examples: k, g, and the velar nasal /ŋ/ (as in “sing”). The /w/ sound can involve a dual articulation with lip rounding and a velar constriction.
  • Glottal: place at the glottis, involving the vocal folds; includes:
  • /h/ (glottal fricative) where vocal folds are open and air flows through.
  • Glottal stop /ʔ/ (not a phoneme in English per se but a common allophonic variant in certain contexts).
• Context and coarticulation effects:
  • The exact place can shift slightly depending on adjacent sounds (e.g., the K in “key” vs “cop” differs due to the following vowel).
  • You may see the same symbol used for different sounds in different contexts depending on surrounding vowels (coarticulation).

Examples and demonstrations mentioned

• S vs Z test to feel voicing differences; Z shows vocal fold vibration.
• Whispering as a non-voiced speech style; verify by placing hand on throat while whispering.
• S vs Sh inhalation exercise to locate front vs back tongue positions:
  • Inhale while producing /s/ and /ʃ/ to feel the difference in tongue positions.
• Quick exercise to feel key vs cop articulation:
  • “Key” engages more front tongue contact; “cop” engages more back contact due to following vowel; tongue body rolls a bit forward and back during the transition.
• Place-of-articulation review image guidance from midsagittal views; demonstrates active vs passive articulators; shows how airflow is shaped.
• Velum and nasalization concept:
  • Nasal sounds (e.g., /m/, /n/, /ŋ/) involve lowering the velum to allow air to flow into the nasal cavity; oral sounds have the velum raised to block nasal airflow.
  • Three nasal places in English: bilabial (/m/), alveolar (/n/), velar (/ŋ/).
  • Contrast with bilabial stop (oral) where the velum is raised and air does not enter the nasal cavity (e.g., the /b/ in “bat”).

Nasals vs. oral sounds (the nasal/oral distinction)

• Nasal sounds: air flows into the nasal cavity; the velum is lowered.
  • Bilabial nasal: lips come together; velum lowered; air resonates in both oral and nasal cavities (e.g., /m/).
  • Alveolar nasal: tongue tip to alveolar ridge; velum lowered; air resonates in nasal cavity and oral cavity.
  • Velar nasal: back of the tongue toward the velum; velum lowered; air flows into nasal cavity.
• Oral sounds: velum raised; air cannot flow into nasal cavity.
• This nasal/oral distinction is one of the key organizing features of English consonants.

Major class groupings by place of articulation

• Labial group: includes bilabial and labiodental sounds (lips involved).
• Coronal group: sounds produced with the front part of the tongue (tip or blade) — includes intradentals, alveolars, post-alveolars, and often the R sound in English (though there is variation in how R is produced).
• Dorsal group: sounds produced with the back of the tongue (velar, and sometimes palatal depending on classification debates).
• Glottal sounds do not fit neatly into these three groups and are treated separately as glottal place of articulation.
• Note on debates: palatal sounds are sometimes argued to be coronal, dorsal, or a separate category; debates exist about whether to classify them with coronal or dorsal due to tongue posture during articulation. The lecturer notes this is not critical for the current course but worth recognizing.

Recap: places of articulation (quick reference)

• Bilabial: both lips; examples include /p/, /b/, /m/, /w/ (lip rounding included), with the lips coming together.
• Labiodental: lower lip with upper teeth; examples /f/, /v/.
• Dental / Interdental: tip protrudes between teeth (American) or rests behind teeth (British); examples typically /θ/ (as in “think”) and /ð/ (as in “this”).
• Alveolar: tongue tip or blade at alveolar ridge; examples /t/, /d/, /s/, /z/, /n/, /l/.
• Post-alveolar: just behind alveolar ridge; examples /ʃ/ (sh), /ʒ/ (zh), /tʃ/ (ch), /dʒ/ (j).
• Retroflex: tongue tip curled back; variant of R sounds; not always used or singularly defined.
• Palatal: tongue toward hard palate; example /j/ (as in “yes”).
• Velar: back of tongue toward velum; examples /k/, /g/, /ŋ/.
• Glottal: at the glottis (vocal folds); examples /h/ and glottal stop /ʔ/.

Nasalization and the role of the velum (revisited)

• Velum (soft palate) controls whether air goes into the nasal cavity.
• When velum is lowered → nasal sounds; when velum is raised → oral sounds.
• The velum can move to allow or block nasal airflow while other articulators shape the consonant or vowel.

Practical implications for learning and phonetics practice

• Understanding places of articulation helps explain why languages differ in consonant inventories and why accents sound different due to coarticulation and tongue/tip position.
• The three major classes (labial, coronal, dorsal) help describe broader patterns of speech sounds across languages.
• Variability between speakers (e.g., tongue-tip up vs tongue-tip down for /s/) is common and expected; it does not necessarily indicate a problem.
• When reading about consonants in IPA, these concepts will guide interpretation of symbols and how to articulate them.
• The next lectures will focus on the International Phonetic Alphabet (IPA) and precise transcription of these sounds.

Quick glossary (key terms used in this lecture)

• Voicing / phonation: whether the vocal folds vibrate during sound production.
• Fundamental frequency: $F_0$, rate of vocal fold vibration; related to perceived pitch.
• Supralaryngeal: above the larynx; encompasses cavities and articulatory processes involved in most speech sounds.
• Pharynx: space behind the tongue; part of the vocal tract.
• Oral cavity: mouth cavity where many speech sounds are formed.
• Nasal cavity: inside the nose; involved in nasal sounds when velum is lowered.
• Velum / soft palate: movable part at the back of the roof of the mouth; raises to block nasal airflow or lowers to allow it.
• Alveolar ridge: the bony ridge just behind the upper teeth; key landmark for many sounds.
• Alveolar / dentoalveolar: front-of-mouth sounds using the tongue tip or blade near the alveolar ridge.
• Passive articulators: stationary structures (teeth, alveolar ridge, hard palate, etc.).
• Active articulators: movable structures (lips, tongue parts).
• Lingual: related to the tongue.
• Nasal vs oral sounds: determined by whether the velum is lowered (nasal) or raised (oral).
• Coarticulation: influence of surrounding sounds on the articulation of a given sound.
• IPA: International Phonetic Alphabet, the system to transcribe speech sounds.