Because no one envisioned sound as a business necessity, the only provision early PCs made for sound was a $0.29 speaker driven by a square-wave generator to produce beeps, boops, and clicks sufficient for prompts and warnings. Reproducing speech or music was out of the question. Doing that required an add-on sound card, and those were quick to arrive on the market as people began playing games on their PCs. The early AdLib and Creative Sound Blaster sound cards were primitive, expensive, difficult to install and configure, and poorly supported by the OS and applications. By the early 1990s, however, sound cards had become mainstream items that shipped with most PCs. By 2001 most motherboards included at least basic embedded audio, and by 2003 it was difficult to find a mainstream system or motherboard without good built-in audio.
With a sound adapter and appropriate software, a PC can perform various tasks, including:
Playing audio CDs, either directly or from compressed digital copies of the CD soundtracks stored as MP3 or Ogg Vorbis files on your hard disk
Playing stereo music, sound effects, and/or voice prompts in games, education, training, and presentation software, as well as for operating system prompts, warnings, and other events
Capturing dictation to a document file, adding voice annotations to documents, or controlling applications using voice/speech recognition software
Supporting audio conferencing and telephony across a LAN or the Internet
Supporting text-to-speech software that allows the PC to "read" text aloud, aiding children who cannot read and people who are visually impaired
Creating and playing back music using MIDI software and hardware
This chapter describes what you need to know to choose, install, configure, troubleshoot, and use a sound card effectively.