Art of Digital Audio, 3rd Edition

3

Digital principles

3.1 Pure binary code

For digital audio use, the prime purpose of binary numbers is to express the values of the samples which represent the original analog sound-velocity or pressure waveform. Figure 3.1 shows some binary numbers and their equivalent in decimal. The radix point has the same significance in binary: symbols to the right of it represent one half, one quarter and so on. Binary is convenient for electronic circuits, which do not get tired, but numbers expressed in binary become very long, and writing them is tedious and error-prone. The octal and hexadecimal notations are both used for writing binary since conversion is so simple. Figure 3.1 also shows that a binary number is split into groups of three or four ...