A simple discrete one-watt amplifier

Here is 'half-watt' (?) amp using one j-Fet & Bjt and it works. Don't know how to do even more simple working amp ...
 

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This is how it gets simpler. Not necessarily better, but simpler. *Ge*t prepared for more germanium.
You used to be able to get 2SB407’s at radio shack. And the rejects they sold had enough ICBo to bias right up.
 

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Somebody wasn’t thinking too well here. “Dim bulbs” only work well when the average current is small compared to the peaks. Not the case in class A, so no real advantage over just a resistor. In class A there is no “going cool” on transients, which would be needed to get increased current swing.
 
Nobody said you had to use a snake oil filled resistor. Circuits as inherently limited as this make absolutely no sense to spend ridiculous money on. I’d just be using four 10 watters in parallel, whatever brand Mouser had on hand. How much inductance can four 10 watt sand box resistors possibly have compared with 8 ish ohms? So they’ve got a bit of steel in them that might magnetize. Get over it, the mosfet has more distortion.

Circuits like this are more about the learning experiences, no the end all be all of hi-fi. Build and be happy.
 
Yes, this one can give say 200mW to 8ohm reistor, but can be listened at low level. Nothing wrong about how it sounds and can be build very quickly also without PCB. Sure no hifi or high-end, but can be fun to build and listen. Long time ago was thinking to build De-Lite with 300W 120V light bulbs and have four of these somewhere and also mosfet's ... which means can't find them anymore and they are very rare now. But these 300Watter bulbs are really big ones🙂