The modern PC sound card contains several hardware systems relating to the production and capture of audio, the two main audio subsystems being for digital audio capture and replay and music synthesis, along with some glue hardware. The replay and music synthesis subsystem produces sound waves in one of two ways:
through an internal FM synthesizer
by playing a digitized or sampled sound
The digital audio section of a sound card consists of a matched pair of 16-bit digital-to-analog (DAC) and analog-to-digital (ADC) converters and a programmable sample rate generator. The computer reads the sample data to or from the converters. The sample rate generator clocks the converters and is controlled by the PC. Although it can be any frequency ...