The LM3886 is one of the most popular gainclone chip amps. It features high power (68WRMS, 135W peak) into a 4-ohm speaker, mute, and simple circuitry, making it an excellent choice for the beginner and professional alike.
I would like to thank bigparsnip from the DIYAudio Forums for designing this PCB and schematic and allowing it to be posted on electroNET.
Build the amplifier following the schematic and PCB. As always, when testing it, test with a cheap speaker that damage to will not cost much to replace.
If your source is consistantly connected (ex. a pre-amp always connected to the amplifier), you can skip C2 by soldering a jumper in place of it on the PCB. If possible I would highly reccomend doing this to decrease signal path and increase audio quality. However, if your source may ever get disconnected (such as a CD player), it is reccomended that you include C2. If you do not, disconnecting the source will send a large DC current into the speaker and will very likely damage it.
Photos of my amp:
Amplifier mounted on aluminum plate (this amp is used as a subwoofer amplifier).