The voice in your computer that lets you know when you've received a new e-mail is made possible by the sound card. Before the arrival of sound cards, personal computers (PCs) were limited to beeps from a tiny speaker on the motherboard. In the late 1980s, sound cards ushered in the multimedia PC and took computer games to a whole different level.

an imageTost of your music collection is probably in digital format, either on CDs or as files on your computer. In order to be able to listen to your music, a sound card converts digital data to analog sound waves you can hear. The output signal is then connected to a headphone or set of speakers. You can also use a sound card to record audio with a microphone. The motherboard on most computer systems has an integrated sound card, which is often sufficient for many users. However, to get higher quality sound you can upgrade to a separate sound card, which uses better and more expensive components.

Uses of a computer sound card

  • Games
  • Audio CDs and listening to music
  • Watch movies
  • Audio conferencing
  • Creating and playing Midi
  • Educational software
  • Business presentations
  • Record dictations
  • Voice recognition

A sound card converts digital data to sound. This allows you to listen to music from your computer using speakers or headphones. Learn about the different types of sound cards and how they work. Audio files on a computer consist of digital data just like any other file on a computer. Sounds we can hear consist of waves that travel through the air - sounds are analog. The primary function of a sound card is to translate between digital and analog information, just like a video card. Sound cards typically have four major components:

  • The digital-to-analog converter (DAC), which makes it possible to convert digital data to analog sound
  • The analog-to-digital converter (ADC), which makes it possible to make digital recordings from analog sound inputs
  • An interface to connect to the motherboard, typically using Peripheral Component Interconnect (PCI)
  • Input and output connectors so you can plug in headphones, speakers or a microphone - many computer systems have speakers and microphone built-in, but connectors allow you to use higher quality external devices to play or record sound.

The picture is an example of a sound card audio ports or audio jacks on the back of your computer, associated colors, and the connector symbols.

  • Digital Out (White or Yellow) (words: "Digital" or "Digital Out") - Used with surround sound or loudspeakers.
  • Sound in or line in (Blue) (Arrow pointing into waves) - Connection for external audio sources, e.g. tape recorder, record player, or CD player.
  • Microphone or Mic (Pink) (Microphone) - The connection for a microphone or headphones.
  • Sound out or line out (Green) (Arrow pointing out of waves) - The primary sound connection for your speakers or headphones. This sound card also has a second (black) and third (orange) sound out connector.
  • Fire wire (Not pictured) - Used with some high-quality sound cards for digital video cameras and other devices.
  • MIDI or joystick (15 pin yellow connector) - Used with earlier sound cards to connect MIDI keyboard or joystick.

Usually the cables connecting to the devices are also color-coded and will match or be close to the colors the cables connect into. For example, the end of the speakers cord may have a green line or be completely green.