If you have the skills and can get your hands on SMD components, you can assemble this small amplifier. We found it in the Radio Electronics Experimenter special edition from 1990.
When the control level is increased from 0 to 1 (LO to HI), this circuit is activated, which...
This 1950's circuit used one of the first commercial transistors and had two stages for audio...
This amplifier can be powered with voltages from 9 to 14 V providing 7W of maximum power under a 8 ohms...