What happens to sound when it is entered into a pc through a mic, and where itis stored?
Natural sound is created when a vibrating body (your vocal
cords for instance) causes an increase and decrease in air pressure.
This "pressure vibration" moves through the air just like the ripples
move through a pond when you throw in a rock. The microphone
contains a very thin diaphragm which vibrates with this change in
air pressure. This vibration generates a voltage which rises and falls
in sync with the physical vibration. A wire carries this voltage
"wave" into the computer and it is fed to a Analog to Digital
converter. This circuit measures that constantly changing voltage
at tiny time intervals ( 40,000 or more times per second )
That measured voltage is stored as binary data just like any other
data on your hard drive. When you listen back to the recording,
the process is reversed. The rapid stream of numbers are converted
back to a varying voltage. Wires carry the voltage to a speaker which
works like the microphone in reverse. The voltage fluctuations go
into a magnet which draws and repels the speakers diaphragm. This
causes a vibration in the speaker to vary the air pressure in the
same way the original sound was created.