All About vintage pro audio
I’ve got concerns that you say you want to build a tube amp, but you don’t appear to understand gain structure. Tube amps are not something that beginners should start out with. You’ll be working with voltages (especially on the power tube plates) that can do some serious damage to you.
That said, preamp distortion is achieved by putting multiple gain stages in series with each other. On some of the older Marshall’s, you will have 4 stages of gain before the phase inverter.
If you want to generate distortion in the power section, then you’ll need to drive them hard from the phase inverter, starve the plates, or both.
Good luck, and don’t hurt yourself.
Greetings from Austin, TX
Ken
Usually designers want to reduce distortion.
do not use any feedback
pick the operating point to be either close to cutoff or close to saturation
add diodes in parallel with signal.
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