An object produces sound when it vibrates in air (sound can also travel through liquids and solids, but air is the transmission medium when we listen to speakers). When something vibrates, it moves the air particles around it. Those air particles in turn move the air particles around them, carrying the pulse of the vibration through the air as a traveling disturbance.

For the structure of a speaker, it may include woofers, subwoofers, tweeters, midranges etc. In general, it has only three major drivers, i.e. a woofer, a tweeter and a midrange. They are to reproduce sound.

In favour of the components of a driver, it consists of a magnet assembly, a metal or composite basket/ frame, coil and cone or dome. Especially, for the coil of wire, it is an electro magnet attached on the amplifier. It has a permanent magnetic polarity that never changes. The magnet is made of ceramic, neodymium or Alnico which is composed of three metals, such as Aluminium, Nickel and Cobalt. In the comparison of the three materials, the neodymium is often used. It is not only cheaper, also lighter and stronger than the others.

The working theory of the coil of wire on a cone or dome is quite complex. First of all, the coil of wire is placed inside the magnet assembly ‘pole piece’. And an alternating signal is placed through the coil. Then, the polarity changes on the coil by the attraction and repellence of the coil within the assembly. Finally, it causes the coil to oscillate. By this way, it is capable for the effective air movement.

For producing sound, a speaker depends on a crossover network which is the basic one for filtering. It is mainly to divide the signals to each driver. Therefore, the bass can go to the woofers. Also, the high frequency can go to the tweeters.

That's why we can conclud that a speaker is like an air pump. The bigger the pump is, the larger the sound is, and the better the sound.

Top