Lecture (2/8) Thursday Week 4 Thursday

Question 1

Complex wave definition

Answer 1

any sound that is composed of 2 or more sine waves

Question 2

How do you find the points on a complex wave?

Answer 2

sum the instantaneous amplitudes of two or more sine waves at each point on the waveform

Question 3

What is a periodic complex wave?

Answer 3

Complex wave that repeats itself over time
(periodic= repetitive)

Question 4

Periodic complex waves are made up of…

Answer 4

frequencies that are harmonically related-not random

Question 5

Describe the harmonic relations of periodic complex waves

Answer 5

each sinusoid must be an integer multiple of the lowest in the series.

Question 6

The highest common denominator of a periodic complex wave sinusoid is called the

Answer 6

fundamental

Question 7

Each of the integer multiples of a periodic complex wave is called a

Answer 7

harmonic

Question 8

in a periodic complex wave, if f0 is 100, what are the other harmonic components?

Answer 8

f0 100
f2 200
f3 300
f4 400
f5 500

Question 9

If the T is 8ms, what is the frequency?

Answer 9

8ms= .008s
1/.008s=125Hz

Question 10

If 125Hz is F0 what are the next harmonics?

Answer 10

2f 250Hz
3f 375Hz
4f 500Hz
5f 625Hz

Question 11

T/F even if F0 is not physically in a complex wave, your brain fills it in.

Answer 11

True

Question 12

What would be the F0 if
3f 600Hz
4f 800Hz
5f 1000Hz
6f 1200Hz

Answer 12

200 Hz

Question 13

Your brain finds the ____ of all the harmonics it hears

Answer 13

greatest common denominator

Question 14

The pitch of the note is also the

Answer 14

f0

Question 15

The octave is…

Answer 15

a doubling of frequency

Question 16

What is the frequency ratio of an octave?

Answer 16

2:1 or 2:1
example: 200:100 or 500:250

Question 17

What is consonance?

Answer 17

adding frequencies that are harmonically related

Question 18

What is dissonance?

Answer 18

adding frequencies that are not harmonically related

Question 19

What happens when you combine frequencies that are close

Answer 19

it creates complex waves that wax and wane in amplitude (beats)

Question 20

Changes in amplitude cause ______

Answer 20

beats

Question 21

The number of beats per second is equal to the _____

Answer 21

difference in Hz between the two tones

Question 22

What is the definition of a Fourier Analysis?

Answer 22

Mathematical process by which a complex sound is broken down into its individual sine waves
(frequency on the x axis and power on the y axis)

Question 23

What does an aperiodic complex wave represent?

Answer 23

combinations of sounds that are not harmonically related

Question 24

characteristics of continuous aperiodic waves

Answer 24

-on going in time
-noise

Question 25

characteristics of transients aperiodic waves

Answer 25

-short duration; brief acoustic event -click

Question 26

the ______ the click, the _______ the spectrum

Answer 26

shorter the click, broader the spectrum

Question 27

What has more frequencies? P= 1ms or P=.03ms

Answer 27

P=.03ms -because it is a shorter period, so it has more frequencies within in

Question 28

What is the psychological definition of noise?

Answer 28

unwanted sounds

Question 29

Which noise has all frequencies of equal amplitude?

Answer 29

white noise

Question 30

Describe gaussian noise

Answer 30

-a type white noise with random amplitudes -amplitudes vary according to a bell curve

Question 31

What frequency emphasis is Sawtooth noise?

Answer 31

high frequency emphasis

Question 32

What frequency emphasis is Pink noise?

Answer 32

low frequency emphasis

Question 33

What is the definition of frequency distortion?

Answer 33

frequencies or amplitudes in the output that were not in the input

Question 34

What will introduce distortion?

Answer 34

a transfer function of energy from one form to another

Question 35

energy transfer is _____

Answer 35

nonlinear (causes distortion)

Question 36

The ear is _____

Answer 36

nonlinaer

Question 37

In distortion, _______ are the frequencies that are added

Answer 37

harmonics

Question 38

Otoacoustic emissions

Answer 38

used to test newborn hearing

Question 39

Tones that are the result of summanation

Answer 39

f1 + f2 ; 2F1+f2

Question 40

Tones that are the result of difference

Answer 40

f1-f2 2f1- 2f2

Question 41

Distortion is measured in

Answer 41

Percentage