Representing Sound

Question 1

Digital

Answer 1

Data that takes form of discrete values

Question 2

Analogue

Answer 2

Data that varies in a continuos manner

Question 3

Sampling Resolution

Answer 3

Number of bits assigned to each sample

Question 4

Sampling Rate

Answer 4

Number of samples per second (Hz)

Question 5

Quantisation

Answer 5

Rounding sample as binary value

Question 6

Process of Sound conversion

Answer 6

Pick up sound wave using microphone
Convert wave into analogue signals
Signals processed by ADC
- taking amplitude at regular intervals
- measurements quantisisdd

To play :
Convert sound from digital to analogue using DAC
signals passed to speaks that vibrates to create analogue sound waves
- analogue waves may differ from original

Question 7

Nyquist Theorem

Answer 7

Sample at frequency at least double rate of highest frequency

Question 8

File Types

Answer 8

MIDI - recording and synthesizing musical instruments
Editable files smaller in size

WAV - used on CDs for editing

MPEG - lossy compression
Removes frequency’s brain and ear will not miss