Audio Devices
Introduction
Audio devices provide sound to a presentation. It maybe a narration, sound
effects, or music. A presentation is ineffective if an audience cannot hear it.
Cassette decks
Cassette decks provide the dimension of sound to a visual presentation. This
music or narration promotes the understanding of the presented material.
Cassette tapes are available in 30-, 60-, 90-, and 120-minute increments.
You can record information on a cassette tape or use pre-recorded tapes.
Some cassette decks require an additional device, called an amplifier, which
increases the sound volume before it reaches a set of speakers.
Nomenclature
Cassette decks have an on/off power switch, a play button, a record button, a
forward/fast forward button, a rewind/reverse button, a pause button, a
stop/eject button, and a tape counter. The tape counter is useful when you
are cuing sound at a specific time or interval and monitoring the amount of
tape expended.
Use
To record, most cassette players require you to depress the record button
simultaneously with the play button. Take care not to re-record over pre-
recorded information. To prevent this, break off the small plastic tab on the
side of the cassette cartridge. Clean the tape heads with a head cleaning tape
or an alcohol solution and cotton swab after 8 hours of play.
Speakers
Speakers transmit sound so that everyone can hear. They use a ground wire
and an input wire for connection to a player or amplifier.
Use
Place speakers far enough from the amplifier to prevent feedback or squeal.
The speakers should remain in front of and facing the audience. Place them
out of the way, preferably mounted on the ceiling.
Care
Keep the front grill of the speaker box. Replace speakers that have been tom
or crushed. Damaged speakers distort sound or buzz and are distracting to
the audience. Occasionally, disconnect the speaker and expose fresh wire to
reconnect to the terminals. Oxidation of the copper core of the wire will
cause the speaker to cut in and out.
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