Digitised Sound

More info

Sound is an analogue signal - a continuously varying wave of air pressure. An ADC (Analogue to Digital Converter) converts this wave into digital data by taking regular samples of its amplitude. Each sample is then encoded using a fixed number of bits, set by the sample resolution.

Adjust the sliders below to see how sampling rate and sample resolution affect the digital representation.

A 4 Hz

B 7 Hz

C 13 Hz

Sample Resolution

4 bits

Sample Rate

18 Hz

Reconstruction:

Below Nyquist threshold — the sample rate must be at least twice the highest frequency in the signal (). At this rate the reconstructed wave is incorrect (aliasing).

Analogue wave

Quantisation levels

Sample points

Reconstructed signal

File size calculator

File size (bits) = rate × resolution × duration

Duration seconds

60 s

Bits

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Bytes

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Kilobytes (KB)

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Megabytes (MB)

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