A sound card (also known as an audio card) is an internal expansion card that provides input and output of audio signals to and from a computer under control of computer programs. The term sound card is also applied to external audio interfaces used for professional audio applications. Typical uses of sound cards include providing the audio component for multimedia applications such as music composition, editing video or audio, presentation, education and entertainment (games) and video projection.
Sound functionality can also be integrated onto the motherboard, using components similar to those found on plug-in cards. The integrated sound system is often still referred to as a sound card. Sound processing hardware is also present on modern video cards with HDMI to output sound along with the video using that connector; previously they used a SPDIF connection to the motherboard or sound card.
In 1984, Roland Corporation released the MPU-401 MIDI Processing Unit, the first MIDI-equipped PC sound card, capable of MIDI sound processing and sequencing. After Roland sold MPU sound chips to other sound card manufacturers, it established a universal standard MIDI-to-PC interface, with a number of sound card manufacturers and most computer software companies supporting the MPU-401 interface. It remained the de facto standard up until the 1990s, when its dominance began diminishing.
- ↑ 1.0 1.1 1.2 MIDI INTERFACES FOR THE IBM PC, Electronic Musician, September 1990
- ↑ Programming the MPU-401 in UART mode
- ↑ MIDI PROCESSING UNIT MPU-401 TECHNICAL REFERENCE MANUAL, Roland Corporation
- ↑ Peter Manning (2013), Electronic and Computer Music, page 319, Oxford University Press
- ↑ David Trubitt (1993), Making Music with Your Computer, page 22