Loudspeaker

A cheap speaker. It is usually in small radios.

A large speaker.

A loudspeaker, which is also called a loud-speaker or speaker, is an item that is used to create the sound in radios, television sets, and electric musical instrument amplifier systems.

How it works

Loudspeakers use both electric and mechanical principles to convert an electrical signal from a radio, television set or electric musical instrument into sound. For a loudspeaker to produce sound, the signal from the radio, television set, or electric musical instrument needs to be connected to an electronic amplifier.

Loudspeakers are usually built by using a stiff paper cone, a coil of thin copper wire, and a circular magnet. The cone, copper wire, and magnet are usually mounted in a rectangle-shaped wood cabinet. The coil of copper wire moves back and forth when an electrical signal is passed through it. The coil of copper wire and the magnet cause the rigid paper cone to vibrate and reproduce sounds.

Inside the loudspeaker can be a audio crossover.

Types of loudspeakers

Some loudspeakers are designed for lower-pitched sounds, such as woofer loudspeakers or subwoofer loudspeakers. Other loudspeakers, which are called tweeters, are designed to reproduce high-pitched sounds (such as the sound of a whistle or a bird singing).

Loudspeakers for electric musical instruments are usually much stronger and heavier than loudspeakers for radios or television sets. Their main function is to convert electrical signals given to it into sound signals.

History

Alexander Graham Bell invented the first audible loudspeaker in 1876. Bell invented the loudspeaker because he needed a device that would amplify sound for the telephone. In 1878, the inventor Werner von Siemens from Germany patented an improved type of electrodynamic loudspeaker which did not yet include an amplifier.^[1]

Loudspeaker Media

Hi-fi speaker system for home use with three types of dynamic drivers
1. Mid-range driver
2. Tweeter
3. Woofers
The hole below the lowest woofer is a port for a bass reflex system.
Kellogg and Rice in 1925 holding the large driver of the first moving-coil cone loudspeaker
A four-way, high fidelity loudspeaker system. Each of the four drivers outputs a different frequency range; the fifth aperture at the bottom is a bass reflex port.
Fostex FE206e (modified) full-range drive unit loudspeaker, using a whizzer cone
Exploded view of a dome tweeter
Electronic symbol for a speaker
Diagram of a Passive Crossover for a Loudspeaker
A bi-amplified system with an active crossover
An unusual three-way speaker system. The cabinet is narrow to raise the frequency where a diffraction effect called the baffle step occurs
A three-way loudspeaker that uses horns in front of each of the three drivers: a shallow horn for the tweeter, a long, straight horn for mid frequencies and a folded horn for the woofer