Digital recording systems have been in everyday use now for nearly 20 years, and such systems have become affordable to the project studio owner within the last decade. But what actually is digital recording, how does it work, and are the claims made about its sonic perfection justified? In the first of this new 6-part series, Hugh Robjohns revisits the technology and techniques involved.
In the third instalment of our series on the techniques and technology of digital audio, Hugh Robjohns turns his attention to digital audio error detection and correction — and some of the problems associated with them!
When an analogue signal is sampled for conversion into a digital data stream, the sampling frequency must be at least twice that of the highest frequency component of the input signal. If this rule is disobeyed, the sampling process becomes ambiguous as there are insufficient points to define each cycle of the waveform. This resulting in unwanted anharmonic distortion component frequencies (not musically related) being added to the wanted signal.