Now before you even read any further. These are not really loud. Just so you know. They are great for sitting at your desk, but you would not want to have them as music for a party or anything. Now you could make a larger more powerful amp, but I didn't. Just FYI.
Here is a video of it playing with the MP3 player I made.
Step 1: Getting everything you wil need....
Then you will need the following:
One NES game of your choice. I only used Rush N Attack because it was the cheapest one I could find.
Two small speakers that will fit into an NES game. 1 Watt 8 ohm. ((0.5 watt are better.))**
Two LM386N ICs
Four 100uF caps
Two 100k resistors
Two 1k pot resistors
Two rectifier diodes
One ON/OFF switch ((Just get the smallest one you can.
6-12 votls worth of batteries. I used watch batteries ((6 volts worth)) due to the limited space. You could wire up a 9 volt and just have it on the outside of the game case. But it would look kinda weird. LOL
** I got these speakers out of an old Dell laptop I had sitting around.
Step 2: What do I do with all these bits???
It is simple and effective. Plus its VERY tiny. I did not make mine as small as it could be. I really think that you could fit two into a 9 volt battery casing. LOL I might have to try that for a headphone amp.
Anyway, you just follow the schematic and you should get something like I got. ((look at second pic))
Step 3: Modding the games case...
Also you will need to drill out the spot for the switch. and the holes for the volume controls.
Just look at the pics to get an idea of what to do. Its really easy.
((YES I KNOW MINE LOOK BAD)) I was way too tired when I did it. LOL I also found out that the little circular saw blade of a dremel, WILL in fact cut through your shirt and into your flesh. So BE CAREFUL!!! ROFL
Step 4: Putting it all together...
First, glue the speakers and the amps in. Put them on separate sides.
Then glue in the batteries.
Now you just have to hook up the power wires to the switch and the Diodes. Just wire the diodes in on the ground line of each amp. If you dont, the speakers will whine like crazy.