Allow me to introduce myself, my name is Sal (if you haven't already guessed :-) ) and I love DIY projects. I have built many nixie tube and numitron tube clocks, tube amps and I collect tube radios. I am also into tube audio with 4 Dynaco ST-70 tube amps, Scott 299B and others.
I want to build my son a tube guitar amp soon and when I was surfing the web I found a neat simple guitar amp using a lm386 audio amp IC. Every part can be purchased from Radio Shack, I had everything in my stock except the 25 ohm rheostat for the volume control.
The small speakers were bought at a swap meet, a pair for $1.00
I made it portable using nicad batteries. I put a 2.1mm connector in the back so when you plug in a 12vac wall transformer it will disconnect the amp from the battery and charge the nicads.
I also wired a 1/4" headphone that will disconnect the internal speaker when the phones are plugged in.
The controls are drive (distortion) with the power on/off switch and volume control. There is a blue LED in between the controls.
Here are some photos of it. It puts out about 1/2 watt which is loud enough to have fun with it.