Though it may not look like it, the circuit in this instructable is so easy anyone with even incredibly basic electronic skills can do this. The circuit shown below is actually 2 mono amplifiers (mono is single channel, for those who don't know). You don't even need to know how to solder and almost all the parts can be purchased at the nearest Radioshack.
P.S. The camera that I am using is old and close-up pictures are blurry. Also the microphone on the camera sucks so the circuit will appear to be horrible-sounding, but it actually sounds good when you play it in your room or wherever.
Step 1: Gather Parts
What you'll need:
2- LM386 audio amplifier IC
2- 220uf of greater capacitors
2- 0.1uf polyester capacitors
6- jumper wires
1- 1/8" stereo headset jack
1- 9 to15 volt battery
1- connector for battery
Step 2: The Diagram and Pre-Build Info
This is the schematics for one of the channels. Build two of these. On your jack you will need to know which are your signal wires and which are your grounds. On the next step I will try to show you where to make your connections (how to breadboard the circuit).
Step 3: Build!
Assemble. Use the pictures as i put the notes on them:
1) Put the chips in.
2) Put in the polyester caps as shown.
3) Plug in the jumpers from pin 2 to pin 4 on each chip.
4) Attach jumpers from pin 6 to the positive side of your power supply.
5) Attach the 220uf caps as shown.
6) Connect the headset jack connections.
7) Top view of previous picture.
8) Hook up a jumper from pin 4 to the negative side of your power supply on each chip.
9)Add your battery connector observing polarity.
10) Connect your speakers.
11) Add battery and double check connections
12) Yay! You're done.
Step 4: Have Fun
Here is a video of the circuit in action. Like i said in the beginning of this instrctables, the mic on my camera sucks so the sound quality of the video will be horrible as well, but in real life the sound quality of this circuit is pretty good.