• 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.

Adding a dummy load to prevent amp from being damaged by having no load?

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Just wondering if it would be a good idea to add some sort of a dummy load to the output terminals of a tube amp to prevent damage in case speaker is disconnected for some reason? Also, how big of an load would you need, would a 100-200 ohm resistor be fine for 8 ohm output?
 
No, you need a load which is a bit nearer to the correct value. A series CR might help (like a Zobel network). Best to simply ensure that you don't run without a load.

Yes, plan A is definitively going to be running it with speakers attached at all times. However, accidents can happen, such as a cable coming loose or something. I'd like to a have plan B other than buying a new output transformer. :)
 
I built some dummy loads that I use when warming up an amp or changing from one amp to another.
 

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Is wiring the output as triode safer for the OPT compared to pentode? I would imagine it is if i draw a horizontal loadline (no load condition) on both curves but i maybe missing something. If so, with the expense of some power loss, i think the best foolproof way would be this, no?
 
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