Principle of Audio Sampling

Here is a little more detail of what is going on. If you were to look at an analog audio signal on an oscilloscope the screen might look something like the image below. This is a continuous representation of the amplitude of the sound over a period of time. (The amplitude being the strength of the sound wave over a time period – or the air pressure).

To transform this into a digital audio signal, you measure the amplitude at fixed time intervals. In other words, you take a series of ‘samples’. A fixed number of snapshots per second to represent the analog signal as a series of digital samples.

Thus, the smooth analog signal has been converted into a series of time-sampled signals. The resulting graph looks broadly similar to the analog signal.