Hey everybody. Welcome. Thanks for joining us.
So today we will be talking about
articulatory phonetics.
This is the study of how speech sounds
are produced in the vocal tract.
All of our articulators in our vocal tracts
must work in concert to produce just one speech sound.
This is to say nothing of the complexity
of these motor routines in casual speech.
So just a note, we will be focusing on
the phonetics of spoken languages,
and more specifically consonant sounds in North American English in this video.
So what's the difference between consonants and vowels you might ask.
Well basically consonants involves some
construction of airflow, whereas vowels do not. 
When linguists described consonant sounds,
we use three criteria: voicing, place of
articulation and manner of articulation.
Let's talk about each of these in turn.
Voicing or state of the glottis refers to what
the vocal folds are doing.
When air passes through open vocal folds,
we call these voiceless sounds.
When air passes through vibrating vocal folds,
we call these voiced sounds.
You can feel the difference between voiced and voiceless sounds
by putting your hand right here on your adam's apple if you're male
 or where your adam's apple would be if you're a female.
So produce these two sounds in succession
[s]
[z]
[s]
[z]
Which one produces the vibration?
You should feel that [z] produces a vibration. So it's a voiced sound.
whereas [s] does not
produce the vibration. So it's a voiceless sound.
Place of articulation refers to where in the vocal track
the construction of airflow takes place.
Bilabial sounds are produced with both
lips like [p], [b], [m].
Labiodental sounds are produced with the upper teeth and the low lips such as [f] [v].
Interdental sounds are produced with the
tongue in between the upper and lower teeth such as [θ] [ð].
such as [θ] [ð].
Alveolar sounds are produced with the tongue at or near the ridge right behind upper front teeth
such as [t] [d] [s].
Palatal sounds are produced at the hard palate or the roof of the mouth
such as [ʃ] [ʒ] [j].
Velar sounds are produced at the velum or  soft palate
such as [k] [g].
Glottal sounds are produced at the glottis
or the space between the vocal folds
such as [h] or the catch in the throat as in Batman 
Manner of articulation refers to how the airflow is constricted in the vocal tract.
Stop sounds result from a complete
constriction of airflow followed by a release of that air
such as [p] [t] [k] [b] [d] [g].
Fricatives are sounds produced when the
tongue approaches 
but does not make contact with a place of articulation causing a bottleneck of the airflow.
This gives the sound a friction like quality
such as [v] [θ] [z] [ʃ].
Affricate results from the sequence of stop plus fricative in rapid succession.
So the affricate [ʧ] represents [t] plus [ʃ]
just as the affricate [ʤ] results from [d] plus [ʒ].
Nasal sounds are produced
when the velum is lowered
allowing air to pass through the nasal cavity
such as [m] [n] [ŋ].
Liquid sounds are produced by allowing
air to pass by one or both sides at the tongue
and the tongue itself can move a lot to
shape the sound
such as [l] [ɹ].
Glide sounds are produced with very
little constriction of air flow
so little in fact that they are often
referred to as semi-vowels
such as [w] [j].
And finally we have tap sounds.
Tap sounds are involving rapid flick of the tongue to some place of articulation.
In North American English we only really
have one tap, and that's at the alveolar ridge. 
You can hear the tap sound in the word butter butter.
Notice where we write it with two "t"s in English that your tongue is producing a tap sound there
rather than a full stop. 
So in North American English you say [bʌɾɹ],
now as compared to in received pronunciation
where you say [bʌtɹ] that involves a full [t] stop.
Okay we discussed these three criteria for
describing consonant sounds:
voicing, place of articulation and manner
of articulation.
and when linguists talk about a
consonant sounds they do so in that order
so for example the sound [b] is
considered a voiced bilabial stop.
[s] is a voiceless alveolar fricative.
That's it for this video. Thanks so much
for watching. Hope you enjoyed it.
So please check out our other videos
including articulatory phonetics and vowels
and also how to navigate the
international phonetic alphabet.
See later.
