Microphones

What is Microphones?

Microphones, input device that developed by Emile Berliner in 1877. It used to convert sound waves into electric waves or input the audio into computers. It captures audio by converting sound waves into an electrical signal, which may be a digital or analog signal. This process can also be implemented by a computer or other digital audio devices. The first electronic microphone was based on a liquid mechanism, which used a diaphragm that was connected to a intelligible speech.

                                                         

Regularly, Microphones designed on the basis of directionality. Beside the type of devices. such as, Omni directional microphones are capable of picking up all sounds in an area, but unable to focus on a particular subject with background noise. Bidirectional, directional, and shotgun microphones are beneficial for an interview. However, two unidirectional devices can provide the same effect, like cardioid microphones.

What is the use of a Microphones on the computer? 

• Offers users the option of voice recognition.
• Also used for voice recording.
• It allows users to record sound of musical instruments.
• It enables users to online chatting.
• Allows us for VoIP(voice over Internet Protocol).
• Also used for computer gaming.
• Further more, it can record voice for singing, podcasts, and dictation.

History 

The first microphone invented as a telephone transmitter by Alexander Graham Bell in 1876. It was a liquid device that was not very practical. In 1886, Thomas Alva Edison invented the first practical carbon microphone. The carbon microphone was used transmission and extensively in telephone transmitters until the 1970s when they were replaced by piezoelectric ceramic elements.

The carbon microphone had a limited frequency range, therefore would not reproduce music effectively. In 1916, the condenser microphone developed by E.C. Wente of Bell Laboratories. The Condenser microphones used for radio broadcasting and the first generation of sound motion pictures.

How Microphones Work?   

     

1. When you speak, sound waves created by your voice carry energy toward the microphone. Remember that sound we can hear is energy carried by vibrations in the air.
2. Inside the microphone, the diaphragm (much smaller than you'd find in a loudspeaker and usually made of very thin plastic) moves back and forth when the sound waves hit it.
3. The coil, attached to the diaphragm, moves back and forth as well.
4. The permanent magnet produces a magnetic field that cuts through the coil. As the coil moves back and forth through the magnetic field, an electric current flows through it.
5. The electric current flows out from the microphone to an amplifier or sound recording device. Hey presto, you've converted your original sound into electricity By using this current to drive sound recording equipment, you can effectively store the sound forever more. Or you could amplify (boost the size of) the current and then feed it into a loudspeaker, turning the electricity back into much louder sound. That's how PA (personal address) systems, electric guitar amplifiers, and rock concert amplifiers work.

 Writer: Mr. Krishan Kumar Saini 

Today we have learnt Basics about Microphones. Hope this lesson is helpful for you.