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.
I do not think that a 12ax7 will drive a totem pair power transistors, the transistors has a low input impedance
and the output of 12ax7 has a high ( > 100k ) impedance..
TIP31C only have a low current gain - something like a triple Darlington stage might be needed using biplar devices to get enough current gain (>50000), possibly bootstrapped for greater voltage swing.