SOUND ELEMENT

Question 1

is a physical phenomenon produced by the vibration of matter and
transmitted as waves.

Answer 1

Sound

Question 2

the perception of sound by human beings is a very complex process. It involves three systems

Answer 2

• the source which emits sound;
• the medium through which the sound propagates;
• the detector which receives and interprets the sound.

Question 3

simplest sound we
can hear is a

Answer 3

sine wave

Question 4

Sound waves can be characterized by the following attributes:

Answer 4

• Period
• Frequency
• Amplitude
• Bandwidth
• Pitch
• Loudness
• Dynamic

Question 5

is the interval at which a periodic
signal repeats regularly.

Answer 5

Period

Question 6

is a perception of sound by
human beings, it measures how ‘high’ is
the sound as it is perceived by a
listener.

Answer 6

Pitch

Question 6

measures a physical
property of a wave.

Answer 6

Frequency

Question 7

Musical instruments are tuned to produce
a set of

Answer 7

fixed pitches

Question 8

0 – 20 Hz

Answer 8

Infra-sound

Question 9

20 – 20 kHz

Answer 9

Human hearing range

Question 10

20 kHz – 1 GHz

Answer 10

Ultrasound

Question 11

1 GHz – 10 THz

Answer 11

Hypersound

Question 12

is the measure of sound levels.

Answer 12

Amplitude

Question 13

If the intensity of a sound is 1watt=m2
, we may start feel the sound. The ear may be damaged. This is known as the

Answer 13

threshold of feeling.

Question 14

If the intensity is 10-12watt=m2
, we may just be able to hear it. This is known as the

Answer 14

threshold of
hearing.

Question 15

The relative intensity of two different sounds is measured
using the unit

Answer 15

Bel or more commonly deciBel (dB).

Question 16

means the change in sound
levels.

Answer 16

Dynamic range

Question 17

the range of frequencies a
device can produce, or a human can hear.

Answer 17

Bandwidth

Question 18

Sound waves are ___ while computers are good at handling discrete numbers.

Answer 18

continuous

Question 19

Each sample is represented by a number, the

Answer 19

‘code’.

Question 20

In order to store a sound wave in a computer, samples of the wave are taken.
* Each sample is represented by a number, the ‘code’.
* This process is known as ___

Answer 20

digitization

Question 21

This method of digitizing sound is known as

Answer 21

pulse code modulation (PCM)

Question 22

According to ___ ___ ___, in order to capture all audible frequency
components of a sound, i.e., up to 20kHz, we need to set the sampling to at least twice of this.

Answer 22

Nyquist sampling theorem

Question 23

most popular sampling rate for high quality sound is

Answer 23

4410Hz

Question 24

The most commonly use digital sound format in Windows systems is

Answer 24

.wav

Question 25

Sound is stored in .wav as digital samples known as

Answer 25

Pulse Code Modulation (PCM)

Question 26

use Adaptive Delta Pulse Code Modulation (ADPCM).

Answer 26

.vox

Question 27

MPEG-1 layer 3 audio

Answer 27

.mp3

Question 28

is a proprietary format

Answer 28

RealAudio file

Question 29

Recording and Digitizing sound:

Answer 29

analog-to-digital converter (ADC) digital signal processor (DSP)

Question 30

converts the analog sound signal into digital samples.

Answer 30

analog-to-digital converter (ADC)

Question 31

processes the sample, e.g. filtering, modulation, compression, and so on.

Answer 31

digital signal processor (DSP)

Question 32

Play back sound:

Answer 32

digital signal processor (DSP) digital-to-analog converter (DAC)

Question 33

processes the sample, e.g. decompression, demodulation, and so on

Answer 33

digital signal processor (DSP)

Question 34

converts the digital samples into sound signal

Answer 34

digital-to-analog converter (DAC)

Question 34

controls the hardware device

Answer 34

Windows device driver

Question 35

— the user’s interface to the hardware for configuring the devices.

Answer 35

Device manager

Question 36

- to combine sound from different sources - to adjust the play back volume of sound sources - to adjust the recording volume of sound sources

Answer 36

Mixer

Question 37

— Windows has a simple Sound Recorder

Answer 37

Recording

Question 38

The Windows Sound Recorder has a limiting editing function, such as changing volume and speed, deleting part of the sound.

Answer 38

Editing

Question 39

There is a better way to generate high quality music. This is known as ____. It is a communication standard developed in the early 1980s for electronic instruments and computers.

Answer 39

MIDI — Musical Instrument Digital Interface

Question 40

is a standard specified by MIDI Manufacturers Association.

Answer 40

General MIDI

Question 41

The MIDI ports on musical

Answer 41

in OUT THRU

Question 42

— for receiving MIDI data

Answer 42

IN

Question 43

— for outputting MIDI data that are generated by the instrument

Answer 43

OUT

Question 44

— for passing MIDI data to the next instrument

Answer 44

THRU

Question 45

Each MIDI files contains a number of

Answer 45

CHUNKS

Question 46

two types of chunks

Answer 46

Header chunk Track chunk

Question 47

contains information about the entire file : the type of MIDI file, number of tracks and the timing .

Answer 47

Header chunk

Question 48

— the actual data of MIDI track .

Answer 48

Track chunk

Question 49

There three types of MIDI file

Answer 49

* 0 single multichannel track * 1 one or more simultaneous track of a sequence * 2 one or more sequentially independent single -track patterns

Question 50

two different types of envelop

Answer 50

Diminishing sound Continuing sound

Question 51

gradually die out

Answer 51

* Diminishing sound —

Question 52

sustain until turned off

Answer 52

Continuing sound

Question 53

THE AMPLITUDE ENVELOP

Answer 53

delay attack hold decay sustain release

Question 54

the time between when a key is played and when the attack phase begins

Answer 54

Delay

Question 55

the time from no sound to maximum amplitude

Answer 55

Attack

Question 56

the time envelop will stay at the peak level before starting the decay phase

Answer 56

Hold—

Question 57

the time it takes the envelop to go from the peak level to the sustain level

Answer 57

Decay

Question 58

the level at which the envelop remains as long as a key is held down

Answer 58

Sustain

Question 59

— the time is takes for the sound to fade to nothing

Answer 59

Release —

Question 60

Digital representation of physical sound waves

Answer 60

Digital Audio

Question 61

Abstract representation of musical sounds and sound effects

Answer 61

MIDI