Representing sound: Practice Questions

What is defined as the number of samples taken per second when converting analogue sound into a digital format?

Calculate the file size in bits for a \(10\)-second sound clip recorded with a sampling rate of \(500\) Hz and a sample resolution of \(16\) bits.

A sound file has a sampling rate of \(4,000\) Hz and a sample resolution of \(16\) bits. If the recording lasts for \(125\) seconds, calculate the file size in megabytes (MB).
(Use the decimal prefix: \(1\text{ kB} = 1,000\text{ bytes}\), \(1\text{ MB} = 1,000\text{ kB}\))

In the context of representing sound, define sampling rate and identify the unit used to measure it.

A digital sound file is recorded for 10 seconds with a sampling rate of 2,000 Hz and a sample resolution of 8 bits. Calculate the total size of the file in bytes.

A high-quality mono sound clip lasts for 60 seconds and is sampled at 44,100 Hz with a 16-bit resolution. Calculate the file size in megabytes (MB) using the decimal prefix \( 1 \text{ MB} = 1,000,000 \text{ bytes} \).

Sound is naturally analogue but must be converted to digital form for a computer to process it.
Part A: Define the terms sampling rate and sample resolution.
Part B: State the units used to measure the sampling rate.
Part C: Explain how increasing the sample resolution affects the quality of the recorded sound.

A voice recording is captured with a sampling rate of \( 8,000 \) Hz and a sample resolution of 16 bits. The recording lasts for exactly 20 seconds.
Part A: Calculate the total size of the sound file in bits.
Part B: Convert your answer from Part A into kilobytes (kB).
Part C: If the sampling rate is doubled to \( 16,000 \) Hz but the sample resolution is halved to 8 bits, explain the effect this would have on the final file size.