How Does a Car Stereo Speaker Work?

Sound

To understand how any type of speaker works, you must first learn how sound works. Sound is a vibration that can travel through air, liquid or a gas. Contrary to science fiction, sound can't be heard in space because it is a vacuum, where there is no air. The sound vibrates through the air and hits your eardrum, which your brain turns into noise.

Several components make up a speaker. A car stereo speaker contains a diaphragm, dust cap, voice coil, magnet, spider, basket, connecting wires and suspension (surround). Most normal speakers you see have a housing frame around them. There is an exception in cars. The car is usually the frame. Speakers are put in doors, the dashboard and trunk. Only large speakers have their own housing frame, usually located in the trunk.

Diaphragm Dome and Suspension

The diaphragm is usually cone or dome shaped. It can be made of plastic, paper or metal. A composite of these materials is usually used. The diaphragm is attached to the suspension (surround). This allows the diaphragm to move. The other end is attached to the voice coil. The voice coil is what vibrates the diaphragm. The diaphragm is then able to produce sound waves.

The suspension is connected to the basket, which doesn't move. The voice coil is attached to the basket via the spider. The spider holds the coild in place but lets the coild move back and forth. The basket of the speaker tends to hold everything together. It can be made out of plastic or metal. The basket also plays a role in taking heat away from the coil.

Layout

There are two electric jacks on your car's speaker. Connecting wires run from your stereo to the speker. The jacks are connected to the coil. The coil is an electromagnet, usually made of copper. When the coil gets electric charges, it moves and produces vibrations. The coil can do this because it is located in a magnetic field created by the permanent magnet in the speaker. When you put two positvely charged magnets together, they will push apart. The same thing is happening here. The magnets cause the coil to be pushed back and forth.

Car Subwoofers

Different types of speakers are made for different types of sounds. The three basic types are woofers, midrange and tweeters. Woofers specialize in low sounds, midrange are for the middle sound spectrum, and tweeters are for the highest frequency of sound. If you see large speakers in the trunk of a car, they are most likely woofers. They are there to give the car stereo system more bass sounds. Tweeters aren't as commonly found. They are the smallest type and aren't usually found in cars.