2.06 - Transfer Function of the Vocal Tract

Question 0

The resonator (______) is ______.

Answer 0

Filter

Variable

Question 1

The sound source can be ______, ______, or ______.

Answer 1

Periodic (voicing)

Aperiodic (noise)

Both

Question 2

Resonance is the ______ to an ______.

Answer 2

Vibratory Response

Applied Force

Question 3

A resonator is set into forced vibration by ______.

Answer 3

Another vibration

Question 4

Resonators do not initiate the _______.

Answer 4

Sound energy

Question 5

The vocal tracts acts like a ______. The body of air resonates _______ that has frequencies matching the natural ________ of volume of air.

Answer 5

Resonator

In response to sound

Resonant frequencies

Question 6

Sound Sources have both ______ and _______.

Answer 6

Harmonics

Fundamental frequencies

Question 7

Formants show up on spectrograms as _______. These are the _______.

Answer 7

Bands

Resonance frequencies

Question 8

The resonance characteristics of the vocal tract (and the ear canal) can be roughly modeled after a uniformly shaped ______________.

Answer 8

Tube open at one end.

Question 9

What four things do resonances in an tube depend on?

Answer 9

Are the ends of the tube are open or closed?

How long is the tube?

How is the tube shaped?

How large are the opening on the tube?

Question 10

What is the typical speed of sound in air?

Answer 10

34,400 cm/s

Question 11

How do we calculate the resonances of a uniform tube open at one end?

Answer 11

(twice the integer minus one) times (34,4000 cm/s divided by four times the length of the tube)

F = (2n-1)(c/4l)

Question 12

How do we abbreviate Resonance?

Answer 12

F

Question 13

How do we abbreviate length?

Answer 13

l

Question 14

How do we abbreviate integers? What are they?

Answer 14

n

__ Resonance (1=first resonance, 2=second resonance, etc.)

Question 15

What does “c” stand for?

Answer 15

The speed of sound

Normally 34,400 cm/s

Question 16

What does shaping the vocal tract differently accomplish?

Answer 16

Changes the peaks in resonance

Question 17

The typical male vocal tract is _____ cm long.

Answer 17

17.5

Question 18

The typical female vocal tract is ______ cm long.

Answer 18

14.5

Question 19

Are female vocal tracts just shrunken version of male vocal tracts?

Answer 19

No. They are smaller and shaped differently

Question 20

The typical glottal source for vowels is ______.

Answer 20

Voiced

Question 21

Can noise (hiss) excitation use the vocal tract to be resonated?

Answer 21

Yes

Question 22

Harmonics ______ as they increase in frequency.

Answer 22

Decrease

Question 23

When f0 changes, the spacing between the harmonics ______.

Answer 23

Changes

Question 24

The vocal tract acts as a _____ resonator.

Answer 24

Variable

Question 25

Altering cavity size results in different ______ producing a different _____.

Answer 25

Resonant frequencies Vowel

Question 26

Vowels have around _____ resonance frequencies/formants

Answer 26

7

Question 27

What is the Lack of Invariance problem?

Answer 27

That we recognize speech via acoustic signals that are inconsistant

Question 28

The glottal source is filtered according to the frequency response of the _________.

Answer 28

Vocal tract

Question 29

If the glottal source is voiced, the harmonics of the glottal source at or near the spectral peaks of the ________ are resonated, while those distant from the spectral peaks _______ and become ________.

Answer 29

Transfer function of the vocal tract Lose energy Attenuated

Question 30

The resonator works the same way if the source is _________, _______, or if _______.

Answer 30

Periodic (voiced) Aperiodic (whisper) f0 changes

Question 31

Despite source changes (periodic vs. aperiodic or f0 changes), the resonances ______.

Answer 31

Remain the same

Question 32

What two things most affect resonance frequencies?

Answer 32

The length of the pipe The cross-sectional area of the pipe as a function of length

Question 33

The radiated sound spreads in ______ as it leaves the mouth and the energy is ______ in lower frequencies. By how much?

Answer 33

All directions Reduced 6 dB per octave

Question 34

Why do motor disorders of the tongue create unintelligiblity?

Answer 34

Because you can't change the shape

Question 35

A good ventriloquist or impersonator can intuit how to ______ to match someone else's

Answer 35

Change their vocal tract

Question 36

What is the difference between Harmonics and Resonances?

Answer 36

Resonances are created when the source/signal's harmonic structure is similar to the spectral peaks of the filter. When they are dissimilar they are attenuated.

Question 37

A spectrogram shows tongue changes in the _______.

Answer 37

Formants

Question 38

In speech, your mouth's job is to ________.

Answer 38

Change the shape to make different sounds

Question 39

Narrowband spectrograms show the _______. Wideband spectrograms show the _______.

Answer 39

Harmonics Formants