This must be the simplest audio amplifier that you can build. It consists of only 4 components! The sound quality is not excellent but it’s exceptionally loud when connected to a 8ohm speaker. How loud you may ask. Loud enough to be heard from outside the room with the door open. It’s has the audio quality of a cheap fm radio but if audio quality is not the main concern, this is a simple and good amplifier.
The four components are: LM386 op-amp, and 3 capacitors.
Circuit schematic. I modified this to remove some unnecessary components to make it as simple as possible. C1 is 2.2uF by the way and C3 is equal to 0.1uF.
This might be a good project if you want to put some speakers to your mp3 player or your phone. Don’t expect exceptional audio quality though. Continue reading