Clicks + Trills

February 5, 2014

Announcements and Such1. I’m in the midst of grading Production Exercise #1.

• You should hear something about it by tonight.

2. Production Exercise #2 (on place of articulation and airstream mechanisms) will be posted after you get comments back on Production Exercise #1.

3. We should check out Miriam Makeba’s “Click Song”...

Click Examples• Clicks can be made at five different places of articulation.

• Languages which use clicks as contrastive sounds are exclusively found in southern and central Africa.

• Particularly in the Khoisan languages

!Xoo Examples• !Xoo (spoken in Botswana) contrasts clicks at all five places of articulation

• Note that !Xoo is also a tone language.

• By convention, a [k] appears before all click sounds, to represent the velar closure.

Click Places

Click Cues• All clicks are very high in acoustic intensity

• i.e., loud

• Alveolar and palatal clicks have a transient (short) release

• Dental and bilabial clicks have an affricated release

• Lateral clicks are somewhere in between

Clicks in connected speech

• If you listen to clicks as they are produced in a long sequence of connected speech, you may experience a phenomenon known as perceptual streaming.

Sound file source: http://www.rdg.ac.uk/%7Ellsroach/fue/

Deep Thought Questions#1: Is it possible to make a voiced click?

• Yes.

#2: Is it possible to make an aspirated click?

• Sort of.

#3: Is it possible to make a nasal click?

• Yes.

#4: Is it possible to make an ejective click?

• Sort of.

• Accompanying articulations may be made in conjunction with the click’s velar closure.

Zulu Clicks

• Zulu is spoken in South Africa.

Zhu|hoasi Clicks

• Zhu|hoasi is spoken in Namibia and Botswana.

Airstream SummaryAirflowPulmonic Glottalic Velaric

OUT fricatives, ejectives unattested

(egressive) vowels,

stops, etc.

IN (Tsou) implosives clicks

(ingressive)

Back to Aerodynamics• Aerodynamic method #1: Stops

A. start air flow

• Remember: Boyle’s Law

• And: Air flows from high to low pressure

B. stop air flow

• Just bring two articulators together.

C. release air flow

• Just relax!

• Not an explosion

• Air pressure differences do the work

• Release burst example: Bengali exercises

Another Aerodynamic Method• What kind of sound is this?

• A Trill. A Bilabial Trill:

• Examples from Kele and Titan

• (Island of Manus, north of New Guinea)

How Fast?• Any volunteers?

• Take a look at the waveform

• (Note: period vs. frequency)

• Do we close and relax our lips each time we do this?

• No?

• When air blows the lips apart, why don’t they stay apart?

Bernoulli Effect• In a flowing stream of particles:

• the pressure exerted by the particles is inversely proportional to their velocity

• Pressure = constant

velocity

• P = k / v

• the higher the velocity, the lower the pressure

• the lower the velocity, the higher the pressure

Daniel Bernoulli

(1700-1782)

Bernoulli Examples

• Airplane wing

• Frisbee

• Shower Curtain

• Pieces of paper

• Bilabial trills!

A Trilling Schematic• Lips are closed

• adducted = brought together

• Fad = adductive force

upper lip

lower lip

inside of mouth

outside of mouth

Fad

Fad

Trilling: Stage 1• Pressure builds up inside mouth from compression of lungs

• Pin = Air Pressure inside mouth

• Outside pressure remains constant

• Pout = Air Pressure outside mouth

PinPout = k

Fad

Fad

Trilling: Stage 1• Pressure differential between inside and outside builds up

• This exerts force against the lips

PinPout = k

Fad

Fad

P = (Pin - Pout )

Trilling: Stage 2• Pressure differential blows open lips

• Air rushes from high to low pressure

PinPout = k

Fad

Fad

air

Trilling: Stage 2• The opening of the lips means:

1. P decreases slightly

2. High velocity of air flowing between lips

3. Air pressure decreases between lips (Bernoulli Effect)

PinPout = k

Fad

Fad

Pbl

Trilling: Stage 3• Lips get sucked back together

PinPout = k

Fad

Fad

Trilling: Back to Stage 1• If air is still flowing out of lungs, pressure will rise again

within mouth

• Process will repeat itself as long as air is pushed up from lungs and lips are held lightly against each other

PinPout = k

Fad

Fad

Trilling: Back to Stage 1• Air rushes through the lips in a series of short, regular

bursts

Pin

Fad

Fad