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How would one build an amplified (electronic) megaphone? Answered

Sup guys. Im trying to start buildign an electronic megaphone, but i dont know where to ger started. I've looked online enough on building and amp, but  dont know if using a microphone requires a preamp on it. So far, i have a plastic cone for the physical part, and a 4 ohm 10W mid-tweet speaker to project the sound. All i need is to know if a pocket amp is sufficient to amp a passive mic loud enough over a crowd. I need need any superb audio quality, just something that you can actually hear what is being said. I would appreciate any plans and help. TY

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rickharris (author)2012-04-09

Microphone - Amplifier (lots around if you search for audio amplifier circuit) - Lou8d speaker - Traffic cone cut down to a suitable size.

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SteamOh (author)rickharris2012-04-09

but would a simple lm386 build be enough to amplify to the loudness i want?

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rickharris (author)SteamOh2012-04-10

I don't know because I have no idea how loud you want it to be!.

It will be reasonable I guess - a lot depends on your speaker/input level. Experimentation is the key here the LM386 isn't expensive and your going to get a lot of experience that may lead to to another audio amplifier that is better/different.
have fun.

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steveastrouk (author)2012-04-08

Depends on the mike ! Whatcha got ?

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SteamOh (author)steveastrouk2012-04-08

Oh.... never thought of that. Dont have one yet :b. Any advice on chossing one would be greatly appreciated too. Thank you!

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steveastrouk (author)SteamOh2012-04-09

Try it with a cheap headset mic. They're usually Electret types. Tie one end of the mic to +supply VIA a 10K resistor or something, and take the signal into your amp through a capacitor

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SteamOh (author)steveastrouk2012-04-09

Would a simple lm386 amp build be enough though? The best lm386 i can find has a 1W max output

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steveastrouk (author)SteamOh2012-04-10

If you have a good horn shape, you'll be amazed how little power it takes to be offensive....

Steve

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