Some students and professionals of electronics feel a great liking for audio amplifiers, because since these are very entertaining circuits. Thinking about it, I propose this DIY Audio Project that consists in a small audio amplifier stage, which is able to reinforce a weak audio signal and transfer it with more potency to two small speakers.

This amplifier offers a good sound quality, and it's ideal for amplify audio signals coming from headphone jack of a MP3 player, a radio, a tablet or another audio device of small signal.

About The Circuit

This audio amplifier stage uses as main element the KA2206B integrated circuit; but it can also work with other equivalent integrated circuits, such as the KA22061, LA4180, LA4550, or LA4555; which require few external components to form a full power stage of stereo sound. This circuit provides 2.3 W per channel over 8 Ohms speakers, and it can be powered by a battery or power supply of 9 volts.

The Circuit Diagram

Sound Test

In this video, I presents a sound test of this circuit but using other PCB prototype design. Because speakers aren't mounted in acoustic cabinets, low-frequency tones will not be heard.