IBM Introduction to Hardware & Operating Systems Practice Test

The sound card's connection to external analog devices is primarily facilitated by a Digital-to-Analog Converter (DAC). This component is responsible for transforming digital audio signals produced by the computer into analog signals that can be understood and transmitted by speakers or headphones.

When audio is processed digitally within a computer, the output needs to be converted to an analog format to be output through standard audio devices, as they operate on an analog signal. The DAC plays a crucial role in this process, ensuring the fidelity and quality of playback.

While other components like Audio Codecs can also be involved in this process, the primary function of a DAC is specifically to handle the conversion from digital to analog. This is integral for any external analog devices that operate on analog signals.