Project: The $5 Cracker Box IPod Amplifier

This weekend we built a IPod amplifier to power a small 8ohm speaker for an art project that one of my good friends was doing. Her project involved a metal sculpture that speak a manifiesto to anyone that walked in front of it.

I found the Amp Schematic in the latest MAKE magazine 09 - The $5 Cracker box amplifier.

It ended up costing closer to $20 CAN in parts because when you buy capacitor and resistor you have to buy them in bundles packages of 20 or so. In the end I have enough spare parts to build 5 of these amps for $20.

The directions where a little difficult to understand, they assumed that you have a good knowledge of circuit diagrams. With the help of of this diagram it should be too hard to figure out what to do. I probably would not have gotten it working with out that diagram.

Instead of using a 1/4 mono phone jack I used a mono head phone jack that connects easily to my IPod. I removed the potentiometer, it just isn’t needed for a IPod amp.

A full size schematic and directions can be downloaded from MAKE’s web page. If you run in to problems feel free to leave me a comment I might be able to help you or try the MAKE forums

Parts list

1. A box of some sort or another
2. Toggle switch, single pole single throw
3. 9V battery
4. 9V Battery connector
5. 0.047µF capacitor
6. 220µF capacitor (biggest)
7. 0.01µf capacitor
8. 100µf capacitor
9. Hookup wire, 2 0 or 22 gauge AWG solid core is best.
10. 5KO potentiometer (audio or log taper)
11. 25-ohm (25O) rheostat
12. LM386N audio amplifier
13. 8-pin DIP IC socket
14. Chicken head knobs (2)
15. Prototyping PC board
16. Speaker, 8O impedance
17. 10O resistor
18. 1/4 mono phone jack

Equipment needed

• Soldering iron
• Solder
• Pliers