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Author Topic: Loudest speaker that I can drive with Arduino?  (Read 2866 times)
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Oh, I wish.  We were out of town.  On the fourth day, when the neighbors noticed the problem, water was running under our front door and down an outside wall like a waterfall.  By the time we arrived, the speaker cabinets had ruptured.  That was a painful end to a very good vacation.
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How can I add a quick and easy volume control to this type of amplifier? Can I replace one of the resistors with something like a 100k audio taper pot?
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Yes, sure. It will save a power for low volume.
Depends on the value of your pot, adjust second resistor proportionally.


* amplifier.png (11.95 KB, 800x600 - viewed 11 times.)
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Would I be able to pair a 10k pot with a 10k resistor, or do I need to use 100k or more for each?
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I was thinking how to minimize numbers of components, as circuitry getting bigger with volume control, and come up with this. You can use any pot in range 220 ohm - 10 k ohm.


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I was thinking how to minimize numbers of components, as circuitry getting bigger with volume control, and come up with this. You can use any pot in range 220 ohm - 10 k ohm.

I think your speaker has to be moved to the collector side of the transistor and ground the emitter for that to work.

Lefty

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Moving speaker to emitter I saved a base resistor. It will works ether way, with little less power  when 4 ohm speaker in the emitter .
NB: amplifier has no DC bias, and should be directly connected to "polarized" signal source, like arduino digital/PWM outputs.
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