Megaphones

Microphone is the switch work piece which can transform voice signals into current signals.

The history of Microphone can go back to the end of 19^th Century. Many scientists like Alexander Graham Bell applied themselves to find the better way to get the sound in order to improve the latest invention at there time—telephone. During that time, they invented Liquid Microphone & Carbon Microphone, but these ones did not have a good effect, only could be used constrainedly.

At 20^th Century, many new microphone tech. developed, including the ones largely used today, like Capacitance Microphone & Electric Actuator Microphone.

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Megaphones on Notebook PC or Mobile phones always seem too weak that others can hardly hear the sound from it. Now this can be solved.

Panasonic Company developed a new kind tech recently: Nano Base Exciter. That is to use Nanotech to produce the largest low diapason output. This kind megaphone has a small cubage, but the sound from it will be much stronger than that of other megaphones in market. It can provide twice of volume without distortion. The reason for this is its hole only has a big of nano, which can let air passing freely, and keep the pressure at the same degree.

We hope this tech can be largely used in the following years, not only on the mobile phones but also on Notebook PC or PPC, and then we can avoid the inconvenience made by outside place megaphones or bull horns.

By http://www.megaphoneusa.com