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.
The gain factor of 27 is only 9 with plate impedance of 9K. You would need to use two of them cascaded to drive the 45 or 2A3. I don't have a schematic handy for you but it should not be too difficult to work on one.
1. You will need a medium mu preamp/input tube
2. You will need to bring the impedance down.
You can use some sort of mu-stage. Or 2:1 transfomer, this will devide the impedance by 4.
Probably a better choice would be to use the 27 as a preamp and something else as the driver.
