Speakers
Speakers are the amazing devices that
are used to play all sorts of music and sounds from your computer! They take
the electric signals stored CDs and
Sound
is produced when an object vibrates through the air. When the object vibrates,
it disturbs the air particles around it, which in turn disturb the air particles
around them, which in turn disturb the air particles around them, etc. All
of these air particles carry the pulse of the vibrating object through the
air. These moving particles create different levels of pressure throughout
the atmosphere. Thus, a vibrating object sends a wave of pressure fluctuations
that eventually reach your ear, where your brain converts it to a series of
different sounds.
When
you want to listen to certain music, your sound card will retrieve it from
your computer's hard disk, where it is stored as electric signals. Your speakers
will take these signals and convert them to sound waves, which will travel
to your eardrums!
At
the very heart of speakers are devices called drivers. The drivers are the
mechanisms that produce sound waves.
Inside
the driver is a group of extremely flexible wires called a voice coil. The
voice coil works just like an electromagnet. The wires of the coil are wrapped
around a magnetic metal, like iron. An electrical current creates a magnetic
field around the voice coil. Like regular magnets, the voice coil has two
poles- north and south. Unlike regular magnets, the north and south ends of
the voice coil can switch, depending on whether the electrical current is
positive or negative. In just one second, the north and south ends of the
voice coil can switch many times!
Well,
to create sound waves, the voice coil must be able to move back and forth.
So, how does it do that? The electromagnet is placed near a permanent magnet
(whose poles cannot switch). The north and south poles of the magnets are
attracted to each other. Thus, when the poles of the voice coil switch, the
magnet forces between the electromagnet and permanent magnet are reversed.
This is what makes the voice coil move back and forth like a piston.
When
the voice coil moves back and forth, it pushes and pulls on a speaker cone.
This is a cone-shaped device made out of either paper, plastic, or metal.
Its narrow end is attached to the voice coil. As the cone moves, the air in
front of it vibrates, creating sound waves. The speaker cone can move because
its wide end is attached to a rim called the surround. The surround is responsible
for suspending all of the moving parts of a speaker.
There
are different types of drivers for different pitches of sound. Woofers are
the largest of the three basic drivers, and are used to produce low frequency
sounds. Midrange drivers produce a middle-ranged frequency sound, while tweeters
are the smallest of the drivers. They produce a high frequency sound!
Speakers
bring life to your computer system. Without them, the sounds effects of high-tech
games cannot be heard, you couldn't listen to music or to DVDs. Sound brings
your computer system to a whole new level, and you can only hear the sound
waves because of your speakers!
Continue on to the next section,
Modems
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