Audio Systems: Is there such a thing as an SED?, electrical conductivity, light thanks

Question
Hi:

Is there such a thing as a Sound-Emitting Diode [SED]? I googled "sound-emitting diode". Nothing factual came up. Just a bunch of jokes.

http://www.google.com/search?hl=en&lr=&safe=off&q=%22sound+emitting+diode%22&btn...

An SED is supposed to give out sound in a similar manner to which a LED gives out light.


Thanks,

Green

Answer
Green-

I've never heard of anything like a SED... sounds like someone is trying to be funny.

However, a simple definition of the word "diode" is a device that passes current in one direction much more readily than in the other. Given this definition, you could probably make a case for "sound-emitting diode" being a fancy way to say "speaker." Most electrical diodes are considered semiconductors, and if you twist the words around, you could even make this part of the definition fit the idea of a speaker, since a semiconductor has electrical conductivity in between a conductor and an insulator, and, in a way, a speaker does the same thing, except mechanically.

Hope this helps....