great primer on how tube circuits work. With this info you can pretty much analyse how all tube amps work since they’re all just variations on this theme. Just add more or less stages, more or less interstage filtering, different component values, etc.
Now we can look at the JCM800 preamp and see why it’s so bright, look at all the treble peaking on every divider, and the small bypass cap on the first stage. Wouldn’t take much to make it way higher gain too, could change the second stage to a more traditional gain stage (or just copy the first one) and bypass cap on the final stage.
Also I clearly don’t browse enough here I didn’t know you made kits for the space heater, it’s such an exploitable circuit also, easily could be modded to whatever type of gain stage you want for a ‘V1’ in front of an amp to make it high gain. And I see you’re sending PCB’s to musicding, that’s good for me!
