Scope

Unlike the Apple Macintosh, the original IBM-compatible PC - which was, after all, designed as a business tool rather than a multimedia machine - did not include a dedicated sound chip in its architecture. In the absence of an official audio standard, Singaporean company Creative Labs stepped into the breach with the release of it's first Sound Blaster card in 1990, and has remained there ever since.

Creative's Sound Blaster AWE cards - first a 32-bit version and later a 64-bit version - had been dominant in the sound card arena, but as overall system performance improved, the ISA bus was soon to become an impediment to audio quality. PCI audio chips began to emerge in the mid-1990s, and in mid-1998 Creative launched it's ground-breaking Sound Blaster Live!, establishing the trend for PCI-based cards with enhanced features for both gaming and music applications.

Originally, audio processing and signal conversions were performed by the sound card in an entirely analogue domain, analogue signals eventually being passed to system speakers as either a single or dual stereo outputs - typically via a 1/8in minijack. Subsequently, sound cards were able to perform their audio processing in an entirely digital environment, outputting either an analogue or a digital signal, the latter being converted to analogue by a decoder in the speaker subsystem. There is much electromagnetic interference (EMI) within a PC's system case, and hence the considerable potential for analogue audio signals to be affected by noise. The emergence of digital speakers in 2001 allowed the conversion allowed the conversion from digital to analogue to be performed in relatively EMI-free environment, thereby significantly improving overall sound quality.