In most small audio projects, hobbyists are using specialized audio amplifier chips. That’s really fine; you get high-quality amplification without scratching your head. Some probably don’t care how these things work. But don’t forget that amplifiers can be built out of discrete electronics components like bipolar transistors. Check out this great hack week project where Dino makes a class AB audio amplifier out of three bipolar transistors and other passive components.
He slightly goes through the theory of operation and, of course, demonstrates its working in the following video.
To be quick… The class AB amplifier consists of two amplification transistors NPN and PNP, where the transistor amplifies the positive side of the signal while another negative. This way, we get the push-pull effect. So don’t afraid to build discrete circuits – they are fun, and you learn a lot. And who knows, maybe your next project will have an amplifier out of discrete components.