"Oversampling" is a term used to indicate a processing technique that is improved by using a sampling rate larger than the minimum rate dictated by the sampling theorem. In this lesson we will examine two types of oversampling

• in oversampled A/D we increase the sampling rate in order to compensate for the use of a cheap quantizer

• in oversampled D/A we increase the sampling rate in order to compensate for the fact that an inexpensive interpolator will not use a sinc kernel

Oversampled A/D and D/A are very clever techniques that exploit the inexpensiveness of digital processing to reduce the cost of the analog electronics used in the conversion. Once again, the enormous success of digital signal processing is also due to the fact that a simple quantitative change (increase the sampling rate) can compensate for a qualitative deficiency (cheap analog circuits). Arguably, for instance, oversampled D/A is the force behind the ubiquity and affordability of digital audio devices.