Make a Speaker and Amplifier Without Complicated Electonics

For a while now I have wanted to make an audio amplifier, but I haven't really had any good opportunities or means to the end. When I found out about the Mono Audio Amp Breakout from Sparkfun, I started to get exited. Its perfect for what I wanted. It's effective and soldering in the right wire is no more difficult than setting up a regular sound system. Not to mention how great it looks in that laser cut mirrored acrylic case. Enough Talk. What does it sound like?

Step 1: Materials and Tools

Hardware
1 USB micro jack
2 Potentiometers, not logarithmic, mine are logarithmic and there is a narrow range of control now
2 Mono Audio Amp Breakout Boards
Solder
1 Switch
1 3.5 mm jack
Wire
8 bolts and nuts of appropriate sizes

Tools(This is what I used, you could probably get away with less)
Soldering Iron
Drill
JB weld
Sand paper
Helping hands are practically a necessity, but if you are dextrus enough you might slide by without them
Chisel and hammer, Theses come in really handy when I find out my laser cut design wast good enough, which is often.

Step 2: Design.

There is a great Google Sketchup Plugin by flightsofideas which makes an SVG file from 3D designs in Google sketchup. You can find the Instructable here.
Anyway, I designed how I wanted the box to be using sketchup and then transferred the faces to an SVG file and put them on the Ponoko P2 laser cutting template.

Step 3: Prepare the Laser Cut Acrylic

I got it the acrylic laser cut at Ponoko. After it came I removed it from its protective layers and tested them for fit.

Step 4: Soldering Most of It

I connect a wire running from the ground wire on the USB jack to the ground pins of the mono Amp and the negative pin of the switch. Don't forget to put the switch through the hole before soldering.
Next I connected the positive voltage to the opposite end of switch.
I then connected the potentiometers to the appropriate holes on the mono amps, that is either edge pin to either edge hole, and the middle pin to the middle hole.
I connected the pins of the audio jack to the appropriated pins of the mono amps. That is the pin the pin with the hole is the negative wire, and the two pins that comes up and bends are positive (look at the pictures for help). Connect the different positive pins to different mono amps but connect the negative pin to both.
I fed the speaker wires through both of the holes, and then soldered them into the audio out pins.
Makes sure everything is connected and makes sense.
We are ready to test!

Step 5: Test 1

Check everything one more time, than plug the USB into a computer USB port and the speaker into a speaker output. Look for a headphones output. Then play some audio!

Step 6: Shrinkify

And now, because I have A LOT of extra wire, I needed to get less of it to fit it inside the box, so I cut the wire in two places, striped it, twisted it together and soldered. Then I covered it with electrical tape to keep it from shorting out. Repeat for all the long wires.

Step 7: Second Test

And now, another test of the speakers before it it all put together.

Step 8: Adjust and Glue

There are little pins on the potentiometers that keep them from spinning behind the acrylic. I put them into the appropriate laser cut holes and where the pin hit the acrylic, I made a mark with a sharpie. Then I drilled part of the way into the acrylic from the back, and tested it to make sure it fit.
Then I cut some necessary slots for the USB, and drilled partway from the front into the audio jack hole, this is for the little provided bolt. Be sure to drill in far enough or else the jack wont go in all the way, but not to far, or else it is much harder to affix to the acrylic.
Now start gluing! only glue the USB, audio jack and on/off jack. I used JB weld for all the parts going into the hole, and then I used hot glue for putting the box together. When there is one side left, put glue on the joints and push them together. After the glue dries, use a hobby knife to clean it up. When both boxes are glued, put glue on the side of the smaller box with the hole and push it onto the bigger box so that the holes of the speaker wires line up.

Step 9: Make It Look Nice.

If the light on the switch doesn't work 100 percent of the time (like with mine) you can put Sugru on the switch. Changes are you probably have some extra Sugru. May I suggest mending your 100% penguin Sugru phone case, or a wire holder.

Now time for a cable holder. Make some holes at each corner, and a trapezoid piece from the top. Then cut some slits into the holes. look at the pictures to see how to use it.