1.Digitising sound

Multiple Choice

sound that is recorded or used by a computer.

• Podcast

• Teaser

• Record

• Digital Audio

Multiple Choice

Why is it important to understand how sound is digitised in modern computing applications?

• Because it helps us appreciate music more

• Because digitised sound is used in many creative and technical fields

• Because analogue sound is no longer used

• Because computers cannot process analogue sound at all

Match

Match each term to its correct description:

• Example of a digital audio broadcast that transmits sound in digital form

• The process of converting analogue sound into digital form by recording at regular intervals

• Sound stored in binary format that can be used by computers

• Examples of digital audio file formats used for storing sound

• Continuous sound captured by a microphone (e.g., vinyl, cassette tape)

DAB radio

Sampling

Digital recording

mp3 / WAV

Analogue recording

• DAB radio

• Sampling

• Digital recording

• mp3 / WAV

• Analogue recording

Multiple Choice

What does the sample rate in digital audio measure?

• The number of bits used to store each sample

• The number of times audio is measured and recorded per second

• The volume of the sound

• The number of channels used in the recording

Multiple Choice

Which of the following statements about sample rate and bit depth is correct?

• Sample rate is the number of bits used to store each sample

• Bit depth is the number of times audio is measured per second

• A higher sample rate creates a more accurate recording

• Standard bit depth for high-quality audio is 44,100 bits

Drag and Drop

The number of times per second the audio is measured and recorded​

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The number of bits used to store each sound sample​

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Standard sample rate for high-quality digital audio​

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Standard bit depth for high-quality digital audio​

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Open-source audio editing software used for editing, conversion, and effects​

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Drag these tiles and drop them in the correct blank above

Sample rate

Bit depth

44,100 Hz

16 bits

Audacity

Match

Match each term to its correct description:

• The height of the wave showing how loud the sound is

• A visual representation of how sound changes over time

• Represents amplitude or the loudness of the sound

• Represents time passing in seconds (also known as frequency)

• The number of sound wave cycles per second

Amplitude

Sound waveform

Y-axis

X-axis

Frequency

• Amplitude

• Sound waveform

• Y-axis

• X-axis

• Frequency

Multiple Select

Select all the correct statements about sound waveforms:

• Amplitude represents the loudness of a sound

• Frequency is shown on the y-axis of a waveform chart

• A high pitch sound has short gaps between waves

• A quiet sound has high amplitude

Drag and Drop

The number of oscillations per second is called the ​

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. It is measured 

in ​

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(Hz) 赫兹. 100 Hz=100 oscillations in one second




Different frequencies sound different to the ear. You hear high frequencies 

as high notes: musicians say that they have a ​

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高音调. You hear low

frequencies as low notes: they have a ​

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低音调.

Drag these tiles and drop them in the correct blank above

frequency

hertz

high pitch

low pitch

Match

Match each type of sound to its waveform characteristic:

• Short gaps between waves (high frequency)

• Low amplitude

• High amplitude

• Longer gaps between waves (low frequency)

Loud sound

Quiet sound

High, sharp pitch sound

Low, soft pitch sound

• Loud sound

• Quiet sound

• High, sharp pitch sound

• Low, soft pitch sound

Dropdown

Contains two separate audio channels for higher-quality sound​​ ​

Select answer

Contains a single audio channel​ ​ ​

Select answer

Requires more storage space​

Select answer

Always record at the highest quality because lost information can’t be restored​

Select answer

Multiple Choice

High Amplitude =__________________

• Louder sounds
• Quieter Sounds

Multiple Choice

Low Amplitude = ______________

• Quieter Sounds
• Louder sounds