M-Audio Dman PCI [27/29] Appendix b digital audio terms

Appendix B - Digital Audio Terms

A/D and D/A converters: A/D stands for Analog-to-Digital and D/A means

Digital-to-Analog. The higher the bit rate and the greater the sampling rate,

the better the audio reproduction. DMAN PCI specifications are equivalent or

better than most audio CD players.

DSP: An acronym for Digital Signal Processor. DSP’s are processors that are

specially tweaked for computation-intensive applications such as playing and

recording audio and audio effects.

Dynamic Range: The ratio between the quietest and loudest sounds that can

be recorded without distortion. Usually measured in decibels (dB).

Full duplex: The ability to record and playback at the same time. Also known

as “simultaneous playback/record.” If you are using a multi-track digital

recording program, such as Samplitude, SAW, or Cakewalk Audio, this is a

very important feature. Full duplex would, for example, allow you to hear pre-

viously recorded vocal tracks while you’re recording the harmonies, a must for

workable audio recording.

MPU-401: A standard for MIDI interfaces, developed by Roland Corporation,

back in the early days of MIDI. This is the most common PC MIDI interface

used under DOS. Under Windows, MPU type interfaces run in UART (some-

times called “dumb”) mode.

Windows Sound System (WSS): Microsoft released the Windows Sound

System audio adaptor in 1992. Its features included a 16-bit stereo A/D con-

verter, 16-bit stereo D/A converter, data compression and de-compression,

analog audio mixing, microphone and line-level input, line-level output and a

high-throughput system interface. Some compatibility with it still remains in

today’s Windows operating system.