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DIY Portable Speaker Amplifier using LM386

For one of my first audio circuits, I decided to make a simple amplifier circuit based on the LM386 IC to power an 8 Ohm 0.5 W Speaker. I started off based on the schematic provided in this instructable:

http://www.instructables.com/id/Portable-Speaker-1/?ALLSTEPS

But once I was done with it, I wasn’t really impressed with the audio quality. The audio would start to crackle really soon and there was very little clarity. As it turns out, all I had to do was add a 0.047 uF capacitor at the output and a 0.01uF capacitor  at the input as decoupling capacitors to get a remarkable upgrade. The more common schematic for this application was available at:
http://www.instructables.com/id/Make-a-Simple-Audio-Amplifier/

Oh and for anybody interested in making this project, do check out this awesome detailed post and video by Hackaday:
http://hackaday.com/2011/05/01/lm386-altoids-tin-amp/

and the original hackaweek post:
http://hackaweek.com/hacks/?p=131

So effectively the schematic I used resembles:

(http://hackaweek.com/hacks/wp-content/uploads/2011/04/LM386ampschematicfinal1.jpg)

In order to test my amp, I even wanted to try using an Arduino to drive this speaker instead of the usual annoying Piezo Buzzer I’d used so far for audio output. I used the sample code from the tutorial dealing with the tone() function in Arduino:
http://arduino.cc/en/Tutorial/tone

Here are some pics of my implementation:

And here’s how it sounds:

Future Plans:
1. Adding a bass boost as mentioned in the reference post
2. Trying out a guitar input and output to headphones
3. Putting it in a case

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