Digital Sound & Music: Concepts, Applications, & Science, Chapter 5, last updated 6/25/2013
Figure 5.2 Analog and digital components in a DAW
Understanding the digitization process paves the way for understanding the many ways
that digitized sound can be manipulated. Let’s look at this more closely.
18.104.22.168 Two Steps: Sampling and Quantization
In the realm of sound, the digitization process takes an analog occurrence of sound, records it as
a sequence of discrete events, and encodes it in the binary language of computers. Digitization
involves two main steps, sampling and quantization.
Sampling is a matter of measuring air pressure amplitude at equally-spaced moments in
time, where each measurement constitutes a sample. The number of samples taken per second
(samples/s) is the sampling rate. Units of samples/s are also referred to as Hertz (Hz). (Recall
that Hertz is also used to mean cycles/s with regard to a frequency component of sound. Hertz is
an overloaded term, having different meanings depending on where it is used, but the context
makes the meaning clear.)
Quantization is a matter of representing the amplitude of individual samples as integers
expressed in binary. The fact that integers are used forces the samples to be measured in a finite