• 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.

Drawing load lines for parallel PP OP stages.

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Both Toobz are swinging 58.94V, their plates are connected together. The 43.09V is the DC cathode potential at the cathode of the 45, ideally it would not move at all. A large cap helps in that location.
I missed labeling that cathode meter, there should be DC affixed to it. Losses in caps in this position could be a problem, especially if they are old or defective.
OTOH, a cap at the input of a capacitor input filter for a rectifier is a concern, designers worry about ESR, the Effective Series Resistance which is inherent in the capacitor build. If the cap is old or defective heat is developed, I've had the odd one explode. This can happen with old stock. That can often be avoided by subjecting the cap to a forming process, driving from a voltage somewhat below its spec thru a current limiting resister. This often takes several hours, go away for two coffees!:)
Google capacitor ESR, there is plenty of info.
 
No? I (re)form caps with more current (25-30mA) in shorter time without limiting resistor. Observe the current for runaway and back of the voltage if it does. Elektrolyte should not boil, so feel the internal temperature. Hinting at actual events (youngsters fighting the police in the Netherlands) there might be an explosion if one is not careful.
 
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