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.
BTW: If you bypass R5 & R3 with the 330uF, you also by-passed the boot strapping feature that Mr Bates put it on this design. Not that this circuit need it IMHO but may be good to know.
Can anybody tell me what is the attraction to this amplifier in its original configuration or even close to the original one?
Especially if you do not have one.