Audio files are used extensively in the creation and manipulation of multimedia presentations. Additional hardware may be needed when working with audio.

Input Hardware

Microphone - used for capturing sounds.

Electronic keyboard / MIDI Interface - used for input and output of MIDI signals.

Manipulation Hardware

Sound board/card - must be capable of 16-bit analogue to digital conversion and 16-bit digital to analogue conversion sampling at 11, 22 and 44 KHz. The board must also have a music synthesiser capable of frequency modulation and wavetable synthesis, as well as on-board analogue audio mixing.

Output Hardware

Loudspeakers - used for playing back audio.

Cassette recorder - for recording analogue version of audio

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Answer the following questions in your jotter.

1. Name three manufacturers of sound boards?

2. How many speakers are needed for surround sound?