Here we are going to know how speakers make noise? And what is the structure of loudspeakers? And What is inside a loudspeaker?
How many times a day do you listen to music playing on the radio, on TV, in shops, in elevators – even in the streets and communities. These are some of the electric gadgets that make sound with the help of a loudspeaker. But what exactly what are loudspeakers, and what is the structure of loudspeakers? And how do loudspeakers work?
Loudspeakers: It is an electroacoustic transducer that converts electrical audio signals into a uniform sound. All loudspeakers, whether small or large, use an electromagnet mechanism to pump sound waves.
The first Loudspeaker uses electromagnets because large, powerful permanent magnets were generally not available at a reasonable price. The coil of an electromagnet, known as field coil, was energized by a current through the second pair of connections to the driver. This winding often served a dual role, performing additionally as a choke coil, filtering the power supply of the amplifier that the Loudspeaker was connected to. AC ripple in the current was attenuated by the action of passing through the choke coil. However, AC line frequencies tended to modulate the audio signal going to the voice coil and added to the audible hum.
Parts of a Loudspeaker
Diaphragm (cone): Moves out and in to push air and make a sound.
Dust cap (dome): It keeps dust and dirt out of the voice coil,
Surround A bit of elastic rubber, foam, or textile that flexibly fastens the diaphragm to the basket (outer body). The surround joins the cone to the chassis.
Basket: The sturdy steel framework around in which the speaker is constructed.
Spider (suspension): A versatile, corrugated supports that keeps the voice coil where it should be.
Voice coil: The coil that moves the diaphragm back and forth.
Front plate: Also made of soft iron.Cables: Connect the stereo amplifier unit to the voice coil.
Magnet: Typically made out of ferrite or highly effective neodymium.
Backplate: Made of the soft metal iron.
Pole piece: Concentrates the magnetic field produced by the voice coil.
How do loudspeakers work?
The Loudspeaker consists of paper or plastic molded right into a cone shape referred to as ‘diaphragm.’ When an audio signal is applied to the Loudspeaker’s voice coil suspended in a round hole between the poles of a permanent magnet, the coil moves quickly backward and forward due to Faraday’s law of induction. This causes the diaphragm connected to the coil to move back and forth, pushing the air to create sound waves.
In their simplest form, loudspeakers use an electromagnet to move a cone-shaped membrane that vibrates to make noise. Inside the speaker, the electromagnet is placed in front of a fixed, ordinary magnet.
As electricity passes through the coil of the electromagnet. The direction of the magnetic field rapidly changes. This causes the electromagnet to continually be repelled by and attracted to the regular magnet, moving the cone-shaped membrane back and forth. The membrane pushes and pulls the surrounding air molecules, creating waves of sound reaches your ear.
The pitch of the sound is governed by the frequency of the vibrations, while the volume is controlled by the amplitude, or height, or the sound waves. Some speakers use multiple cones of various sizes to replicate the different frequencies in a piece of music.
This was a little explanation about Loudspeakers, what inside a loudspeaker, and how it works. All are explained clearly and briefly but in a small part in this article.
Do you want to know about SpaceX reusable rockets and also want to know about how do they work, then check this article: How do SpaceX reusable rockets work?