Audio Requirements For Microsoft's PC-99

Microsoft developed the PC-99 specification to define consistent architecture and performance requirements for Windows-based PCs. Chapter 17 of the specification deals with audio requirements. The PC-99 audio specification covers:

• Audio system requirements;
• Audio performance and feature requirements;
• Advanced audio recommen-dations.

The PC-99 document specifically defines minimum performance requirements for frequency response, THD+N, and crosstalk. It defines system requirements such as nominal signal levels and input impedances as well. The specification covers physical interfaces, like the type of connectors and connector color-coding for interfacing the audio with the outside world. To obtain the PC-99 specification online, visit www.microsoft.com/hwdev/pc99.htm.