Manner of articulation

Manner of articulation describes how a speech constriction controls airflow. A plosive builds an oral closure that can be released; a fricative narrows the passage enough to generate turbulent airflow. A nasal consonant can close the oral passage while allowing air to pass through the nose.^[ref]

Compare [p], [f] and [m]. Their differences cannot be reduced to whether the sound comes from the front of the mouth: the closure, friction-producing narrowing and nasal route produce different acoustic consequences. A sustained [f] contains a noise component generated by airflow through a narrow constriction; a sustained [m] combines voicing with a different resonant airway.

Manner of articulation complements place of articulation. Two sounds can share a place but differ in manner, so identifying only the location of a constriction leaves the mechanism underspecified.

An affricate is a consonant with a complete closure followed by a fricated release, treated as one coordinated sound in the analysis of a language. It combines a stop-like beginning with turbulence during release. This manner of articulation differs from a freely combined consonant cluster containing a plosive and a fricative.^[ref]

English jet begins with the affricate [d͡ʒ]; chair begins with [t͡ʃ]. The tie in these transcriptions signals the intended grouping. A recording can reveal the closure and following frication, but those phases alone do not settle whether a language organizes the sound as one unit or two. Contrasts, distribution and articulatory coordination provide further evidence. Counting written letters is especially unreliable: the two letters ch can represent one affricate.

A plosive is an oral stop consonant: articulators form a complete oral closure, pressure can build behind it, and releasing the closure can produce a brief burst. During the closure, the nasal airflow route is normally closed. This distinguishes the mechanism from a nasal consonant with the same oral place of articulation.^[ref]

The sounds [p] and [b] both use a bilabial closure, while differing in their usual voicing classification. A recording of a released [p] can show a closure interval followed by a burst and the following sound. The release need not always be audibly strong, so an absent obvious burst alone does not show that no closure occurred. Articulation and the observed acoustic trace provide complementary evidence.

A fricative is a consonant produced with a narrow constriction that generates sustained turbulent airflow and its associated noise. The articulators approach closely without creating the complete oral closure of a plosive. Place of articulation and voicing further distinguish different fricatives.^[ref]

Sustain [f] and then [v]. Both use the lower lip and upper teeth, but the second normally adds vocal fold vibration. A spectrogram can display a noise component and, where present, periodic structure. The physical source of the noise is the constricted airflow, while the vocal tract shapes its spectrum. Merely calling a sound unvoiced does not identify it as a fricative.