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4. Plasma Arc Speakers
This kind of speaker is visually quite interesting but limited in sound quality. The speaker has reliability problems and therefore remains just a novelty.

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5. Piezoelectric Speakers
Piezoelectronics are a solid state technology which makes them durable and good for use as a microphone underwater. These speakers are used as microphones in submarine warfare, they can detect other microphones and hear sounds of other vessels.

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3. Flat Panel Speakers:
The standard flat panel electrodynamic loudspeaker has been difficult to make because it is difficult to vibrate the entire flat surface. Thus other speaker types have evolved to try to make a speaker in a flat form.

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2.The Electrodynamic Loudspeaker:
This is a device that uses an electromagnetic coil and diaphragm to create sound. This is the most common type of speaker in the world today.

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1. Horn uses: Audio recording for entertainment and record keeping, later on for voice radio

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1.) Horns

2.) Electrodynamic Loudspeaker
a.) About Sound
b.) Timeline of the Modern Speaker

3.) Flat Panel Speakers:
a.)Planar
b.)Electrostatic
c.)Multi-cell Diaphragm Speakers

4.) Plasma Arc Speakers
5.) Piezoelectric Speakers

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The different between loudspeaker and microphone

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The different between loudspeaker and microphone

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Microphone: acoustical sound energy ➔electrical energy

Loudspeaker: electrical energy ➔acoustical sound energy

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How loudspeaker turns electricity into sound

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How loudspeaker turns electricity into sound

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When things shake about, or vibrate, they make the sounds we can hear in the world around us. Sound is invisible most of the time, but sometimes you can actually see it! If you thump a kettle-drum with a stick, you can see the tight drum skin moving up and down very quickly for some time afterward and this process pumping sound waves into the air. Loudspeakers work in a similar way.  At the front of a loudspeaker, there is a fabric, plastic, paper, or lightweight metal cone (sometimes called a diaphragm) not unlike a drum skin. The outer part of the cone is fastened to the outer part of the loudspeaker's circular metal rim. The inner part is fixed to an iron coil (sometimes called the voice coil, colored orange in the diagram) that sits just in front of a permanent magnet (sometimes called the field magnet, and colored yellow). When you hook up the loudspeaker to a stereo, electrical signals feed through the speaker cables (red) into the coil. This turns the coil into a temporary magnet or electromagnet. As the electricity flows back and forth in the cables, the electromagnet either attracts or repels the permanent magnet. This moves the coil back and forward, pulling and pushing the loudspeaker cone. Like a drum skin vibrating back and forth, the moving cone pumps sounds out into the air.

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A loudspeaker (or loud-speaker or speaker) is an electroacoustic transducer, which converts an electrical audio signal into a corresponding sound.The first primitive loudspeakers were invented during the development of telephone systems in the late 1800s, but electronic amplification by vacuum tube beginning around 1912 made loudspeakers truly practical. By the 1920s they were used in radios, phonographs, public address systems and theatre sound systems for talking motion pictures.