To digitally capture an analogue sound wave, a sound encoder is required:
Band limiting filter - This removes any high frequency components to the sound which the ear cannot hear and may interfere with the eventual sound recording.
Analogue to digital convertor
Analogue to digital convertor:
Sampling resolution = number of different levels whereby the amplitude can be quantified (3 bits = 8 levels(16 bit is lowest value to get a normal representation of the analogue sound)). The higher the resolution the higher the integrity of the recording (combine with sampling rate).
Sampling rate = Number of tests of (sampling resolution tests) per second. Nyquist's theorem suggests that sampling rate should be at least twice as frequent as the maximum sound frequency (at any point in the recording).