Speech Production 1

Stops

• Stops include / p, b, t, d, k, g/ (and glottal stop)

• Stops may be described in terms of …– Manner of articulation– Place of articulation– Voicing

Speech Production 2

Manner

• All stops have same manner of articulation1. Sudden burst of air or sudden stop in the

burst of air.2. All have an aperiodic sound source3. All produced from mouth (as opposed to

nares)4. Rapid changes in articulators result in

rapid change in acoustic resonance.

Speech Production 3

Place

• Place of articulation refers to where the major constriction occurs.

• Bilabial /p, b/• Alveolar (lingua-alveolar) /t, d/• Palatal (lingua-palatal) /k, g/…

– Note: may be velar depending upon vowel context.

• Glottal

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Place

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Spectrograms of Stops

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Voicing

• /p, b, k/ are unvoiced – Contain only an aperiodic component

• /b, d, g/ are voiced– Contain both periodic and aperiodic component

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Fricatives

• Fricatives include • Similar to stops …

– Both contain an aperiodic noise source

– Both have a place of maximum constriction

– Both may be voiced or unvoiced

• Different than stops– Manner of articulation … fricatives involve only a

partial constriction of vocal tract. Fricatives are sometime referred to a continuants.

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Place and voicing

Speech Production 9

Place and voicing

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Speech Production 11

Affricates

• Combination of a stop and fricative .

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Sound Influence

• Adaptation

• Assimilation

• Coarticulation

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Adaptation

• Variations in articulators as they move from one articulator to another resulting in different allophones.– E.g., “key vs. coo” …. /ki/ vs. /ku/ or “pea vs.

pooh” …. /pi/ vs. /pu/– In both instances the production of the stop has

been altered due to vowel context.

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Assimilation

• Extreme form of adaptation where production of phoneme is changed due to context.

• E.g., the word “think”

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Coarticulation

• Two articulators moving at the same time for different phonemes.

• E.g., /tu/. Lips are protruded in anticipation of /u/

• During running speech coarticulation (along with adaptation and assimilation) occur constantly.

Speech Production 16

Suprasegmentals

• Sometimes referred to as prosody.• Provide examples• Give speech its color, expression and sbutle

meaning• Suprasegmentals include …

– Stress– Intonation– Duration and juncture

Speech Production 17

Stress

• Increase in – Effort– Intensity– Pitch– Duration– Formant pattern

Speech Production 18

Stress (continued)

• Acoustic events– Increase in fo

– Formants not affected by adaptation– Higher muscle activity (e.g., emg)– Vowels have longer duration and are of greater

intensity due to increase in subglottal air pressure.

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Intonation

• Change in fundamental frequency.

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Intonation (continued)

• Changing intonation can change meaning & may signal attitude and feelings.– Rising inflection can signal difference between

statement and question.– Flat intonation sometimes implies

“seriousness”– Can denote sarcasm– May indicate excitement, etc.

Speech Production 21

Intonation (continued)

Speech Production 22

Duration and Junction

• Duration– Usually involves changing length of vowel.– May be volitional or involuntary– Vowel before a voiced phoneme is longer than what

occurs before an unvoiced consonant. E.g., wet vs. wed

• Juncture– Combination of changes in stress and duration can

cause change in meaning.– E.g., a name vs. an aim, Contest can mean either

“games”, or a “challenge” depending upon context.

Speech Production 23

Summary