Connectivity

from The PC Technology Guide
bt Dave Anderson

Since 1998, when the fashion was established by Creative Technology's highly successful SoundBlaster Live! card, many soundcards have enhanced connectivity via use an additional I/O card, which fills a 5.25in drive blanking plate and is connected to the main card using a short ribbon cable. In its original incarnation the card used a daughter card in addition to the "breakout" I/O card. In subsequent versions of the daughter card disappeared and the breakout card became a fully-fledged 5.25in drive bay device, which Creative referred to as the Live!Drive.

Connectivity

The Platinum 5.1 version of Creative's card - which first appeared towards the end of 2000 - sported the following jacks and connectors:

Analogue/Digital Out jack: 6-channel or compressed Dolby AC-3 SPDIF output for connection to external digital devices or digital speaker systems; also supports centre and subwoofer analogue channels for connection to 5.1 analogue speaker systems
Line In jack: Connects to an external device such as cassette, DAT or MiniDisc player
Microphone In jack: Connects to an external microphone for voice input
Line Out jack: Connects to powered speakers or an external amplifier for audio output; also supports headphones
Rear Out jack: Connects to powered speakers or an external amplifier for audio output
Joystick/MIDI connector: Connects to a joystick or a MIDI device; can be adapted to connect to both simultaneously

Musical Instrument Digital Interface: a specification that standardizes the interface between computers and digital devices that simulate musical instruments. Rather than transmit bulky digitised sound samples, a computer generates music on a MIDI synthesiser by sending it commands just a few bytes in length. These contain all the information a sound board needs to reproduce the desired sound - the type of instrument, the pitch, duration, volume, attack, decay, etc. are all specified by the protocol. Each channel of a MIDI synthesiser corresponds to a different instrument, or voice. Programming several channels simultaneously produces symphonic sound.

CD/SPDIF connector: Connects to the SPDIF (digital audio) output, where available, on a CD-ROM drive or DVD-ROM .

Compact Disc-Read Only Memory: a standard for compact disc to be used as a digital memory medium for personal computers. The 4.75in laser-encoded optical memory storage medium can hold about 650MB of data, sound, and limited stills and motion video. A CD-ROM player will typically play CD-DA discs, but a CD-DA player will not play CD-ROMs. The standard used for most CD-ROM formats is known as Yellow Book, based on the standard published by Philips.

AUX connector: Connects to internal audio sources such as TV tuner, MPEG or other similar cards
CD Audio connector: Connects to the analogue audio output on a CD-ROM or DVD-ROM using a CD audio cable
Telephone Answering Device connector: Provide a mono connection from a standard voice modem and transmits microphone signals to the modem
Audio Extension (Digital I/O) connector: Connects to the Digital I/O card or Live! Drive and the front panel of the Live!Drive IR device provided the following connectivity:

RCA SPDIF In/Out jacks: Connects to digital audio devices such as DAT and MiniDisc recorders

"º" Headphones jack: Connects to a pair of high-quality headphones; speaker output is muted

Headphone volume: Controls the headphones output volume

"º" Line In 2/Mic In 2 jack: Connects to a high-quality dynamic microphone or audio device such as an electric guitar, DAT or MiniDisc player

Line In 2/Mic In 2 selector: Control the selection of either Line In2 or Mic In 2 and the microphone gain

MIDI In/Out connectors: Connects to MIDI devices via a Mini DIN-to-Standard DIN cable

Infrared Receiver: Allows control of the PC via a remote control

RCA Auxiliary In jacks: Connects to consumer electronics equipment such as VCR, TV and CD player

Video Cassette Recorder: a videotape recording and playback machine that is available in several formats. Sony’s Beta tape was the first VCR format, but is now defunct. VHS 1/2in tape is the most commonly used format. Although VCRs are analogue recording machines, adapters allow them to store digital data for computer backup. See also VHS.

Other sound card manufacturers were quick to adopt the idea of a separate I/O connector module. There were a number of variations on the theme. Some were housed in an internal drive bay like the Live!Drive, others were external units, some of which were designed to act as USB hubs.

Universal Serial Bus: Intel’s standard for attaching peripherals to PCs. Designed for low to medium data throughput, it should remove the need to install many devices internally once it gains widespread acceptance. The original 1995 USB1.1 standard supports a rate of 12 MBit/s, the subsequent USB2.0 standard up to 480 Mbit/s.