I’ve Always Wanted To Know:
How does a speaker work?
Do you have a pair of headphones, a set of desktop speakers or a monster surround system? Do you know how the speakers turn the signal they receive into sound?
A speaker works by converting an electrical signal into vibrations using a speakers diaphragm to produce the sound you hear. The frequency and intensity of the sound is determined by the speed & intensity of the vibrations of the diaphragm.
An electromagnet is placed in front of a permanent magnet and when electric current is applied the magnet pushes or pulls away (depending on the direction of the flow of the current) from the permanent magnet causing the diaphragm to vibrate. The diaphragm, usually made of paper or plastic in a cone shape, then amplifies these vibrations through the air and towards your ears for you to hear.
The speaker unit which produces the sound is called the driver and drivers come in various sizes. Generally speaking, the smaller the driver the less powerful it will be. Headphone drivers are much smaller than home speaker drivers which are much smaller than DJ sound system speaker drivers.
The speed the diaphragm vibrates at dictates the frequency range it will produce. The faster faster it vibrates the higher frequency of the sound, the slower it vibrates the lower the frequency of the sound. Since it is easier to vibrate a larger diaphragm slower than faster and a smaller diaphragm faster than slower the type of driver in a multiple driver speaker unit can be often identified by it’s size.
The larger driver is a low frequency sound driver (woofer), the middle size driver is a middle frequency driver (mid-range) and the smaller driver is a high frequency driver (tweeter). Some high quality sound systems can separate these drivers into completely separate speakers and use them in combination to produce the full audio experience.