Above is a schematic for a simple 12-volt guitar amplifier. I recently simulated this design in Multisim–which came out of Randy Slone’s text Electricity and Electronics–and am having the PCB board manufactured through Advanced Circuits out West. I am actively looking on Craigslist for an old speaker cabinet to retrofit with this board. I’ll talk more about the design as this thing progresses a little further.
Before I do though, I’d like to give a shout out to Randy Slone, who is unfortunately no longer around. His book, referenced above, and the one entitled High-Powered Audio Amplifier Construction Manual, are some of the most enlivened and empowering books I’ve read in the field of electronics. Maybe it’s because he dedicated each of his books to Jesus, or maybe he was just a really nice guy and a great communicator. Either way, I’ve learned tons from him, and doing his 12-watt guitar amp project, I feel connected with his enthusiasm and work.