4.5.6.7 Digital Representation of Sound

Question 1

Digital Representation of Sound

Answer 1

Computers represent sound as a sequence of samples, each take a discrete digital value
~ number of samples per second, measured in Hertz

Question 2

Sample Resolution

Answer 2

Number of bits allocated to each sample

Question 3

High Sample Resolution

Answer 3

Greater audio quality but increased file size

Question 4

Size of Sound Sample

Answer 4

Multiply together the duration of samples in seconds, sampling rate in Hertz, sample resolution

Question 5

Size of Sound Sample Example

Answer 5

A minute long audio file sampled at 44 kHz with a sample resolution of 24 bits would require almost 8 megabytes of storage.
~ 60 x 44,000 x 24 = 63360000
~ 63360000 / 8 = 7920000

Question 6

Metadata

Answer 6

Can be stored in audio file, increase the space required to store file

Question 7

Nyquist Theorem

Answer 7

Sampling rate of digital audio file must be at least twice the frequency of the sound. If the frequency is below this the sound may not be accurately represented .