
the exact scheme I see difficult, look through the datasheet of the valves to the output impedance that works, so that you can get an output transformer, I have used 220 to 12 volt current transformers as a transformer for the small speaker in this In this case, on the part of the 220 you put the plate plate load and on the part of 12 an 8 ohms loudspeaker, as a test at least it is valid, since if you want something precise you have to send it to be done or buy it from the impedances that Use the amplifier tube. regards