What type of sound card do you need to play music files through your stereo system?

To play music files through your stereo system, you typically need a sound card with a line-out or optical output. A standard integrated sound card on most computers can suffice, as they usually have a 3.5mm output that can be connected to the stereo. For higher audio quality, consider a dedicated external USB sound card or digital-to-analog converter (DAC) that supports higher bit rates and sample rates. Ensure the sound card is compatible with your operating system and supports the audio formats you intend to use.