OCR Computer Science - 2.6 - Sound and Data Representation

What is a sample rate?

• The rate a which an instrument is played

• The rate at what a sound card records frequencies

• The speed that the sound card turns on

A microphone converts the changes in air pressure into voltage changes which are then digitised.

• True
• False

The following is true about sampling rates:

• They measure a number of snapshots of sound taken per second.
• They are not as important as bit rates.
• They are different for every song, depending on its loudness.

Identify a false statement:

• Higher bit rates usually improve the sound quality and result in smaller file size.
• Higher bit rates usually improve the sound quality but result in larger file size.
• To record a sound into binary format, ADC will be applied rather than DAC.

the more bits used per sample enables the height of the wave...

• to be more accurately measured

• to be less accurately measured

• increases file size

• decreases file size

Recording quality improves....(pick two)

• the LESS accurately we record the wave height

• the MORE frequently we sample the sound

• the MORE accurately we record the wave height

• the LESS accurately we record the wave height

Our hearing range is measured in.....

• Cycles Per Second

• Hertz

• Fresnel

• Kilohertz

The height of a sound wave is called its amplitude.

• True
• False

Sound is converted to an audio file by taking ‘samples’ of its amplitude at different points in time.

• True
• False

Sound is stored as an analogue file.

• True
• False