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.
From some limited experiments, I found I preferred the sound of an unbypassed cathode resistor as opposed to LED (HLMP6000), but I will need to revisit that at some point.
Me too. One should recognize the situation were the lowered output impedance influences the operation of the final. Diodes do not bring a "preferred sound".
