This is a mini amp I made from parts purchased on Amazon. The total came to about $43 shipped, and there are enough parts to make 2 amps.
Here's the final product with instructions and part links:
This is the little amp chip.
And here's the basic hookup diagram.
These are all the parts used:
And here they are hooked up for testing:
I highly recommend a bigger speaker, however.
One
mod you can do to save money is to remove the 1/8" mini jack and solder
your 1/4" TRS plug inputs directly to the Signal Positive and Negative, as shown below.
If you decide to keep the mini jack, you'll use either a TS plug "tip=+" or TRS "ring=+"
1/4" input(below) is as follows: tip="input +", Ring="battery -", Sleeve="input -".
Be sure to get the battery negative connection correct at the TRS "Ring" so your amp only turns on when a plug is inserted!
Here's another diagram:
Speaker connections:
Battery Positive only
Glue in your battery box:
This is the amp and speaker cabinet I made, but pick your favorite little box that fits all the parts:
Glue in your speaker:
Install and tighten the amp in chassis.
