• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

How is it possible?


Recently i build a little amp with a single ecc83(12ax7)
The both triodes were strapped parrallel without bias circuitry and no anode-load resistor.

Now, it doesn't use an output transformer like normally but a 'ignition coil' or a bobine which makes the hv-sparks for a car...

The thing is although it doesn't go very loud (duh) it Does sound kinda nice especially the mids and high, bass improved a little by using a 12ax7-a.

But how is this possible??? a bobine? i know it works as an auto-transformer, so....

Would this be possible for higher wattages or (as i have read here earlier) a second cheap way for test-output transf??? like the use of a normal mains transformer??

I hope there is someone who can explain this 'magic'
thnx a lot