Representation of Sound 2

Sound waves are analogue data. Computers cannot work with analogue data. So, what needs to be done in order for computers to store sound waves?

• Sound waves need to be sampled. This can be done by an ADC (Analogue to Digital Converter).

• Sound waves need to be recorded.

• Sound waves need to change frequency. This can be done by a SWFC (Sound Wave to Frequency Converter).

• Sound waves cannot be stored in computers from external sources.

What is meant by sampling resolution (bit depth)?

• The number of bits per sample.

• The number of bytes per sample.

• The number of pixels per sample.

• The number of data per sample.

What is sound?

• A ball

• Air wave pressure

• A collection of particles moving in circles

• A number of electrons moving in spirals

What is sampling?

• The number of bits used to represent the sound

• Turning a microphone on and off to only record sound at certain times

• Taking measurements of a wave at regular intervals

• Combining two sound waves into one

What is the sample rate?

• The number of bits used for a sample

• How many times a sound wave goes up and down

• How fast a sound wave moves

• How many samples are taken each second

What is sample rate measured in?

• bits

• Hertz

• Kbps

• Decibels

What does a microphone do?

• Converts analogue sound waves into electrical signals

• Converts electrical signals into sound

• Makes a sound louder

• Records a sound wave as a binary value

If the sample rate and sample resolution are increased, what happens to the sound file?

• Quality goes up. Size of the file goes up.

• Quality goes down. Size of the file goes down.

• Quality goes down. Size of the file goes up.

• Quality goes up. Size of the file goes down.

What factors contribute to poor sound quality? (PICK 2)

• Insufficient bit depth to accurately record the wave height

• Inadequate sampling rate per second

• Not enough sound waves reaching the microphone

• Insufficient duration in each sample

How is an analogue sound recorded?

• Microphone senses air wave pressure

• Amplitude of wave measured at regular intervals

• Amplitude measurement converted to binary

• Binary value stored in file