This is a simple audio amplifier circuit but pretty good output. it runs only with 12v power supply. it can also be used as car audio player only thing is need is vire mp3 player and for that i have included 5v power supply with LM7805 . i have designed this amplifier only for my few friends request as they need a small single speaker amplifier for their car which should be run from 12v supply and most importantly it should be cheap i mean very very cheap. This circuit is designed for only 1 speaker but with same two circuits near each other any one can built a full size car amplifier. All components are commonly available parts. The IC which i used is LA or LM 4440 its very cheap and commonly available and all Variable pots are 47k only the Volume pot its 100k actually its better to use a 100k pot rather than 47k as volume. So built this circuit in a good quality PCB and if you have any problem with this circuit than please communicate with me firstname.lastname@example.org.