Easy Questions for tube amp dummies

[kg]

The failure mode is a damaged primary *caused by* mismatched load on the secondary. Very common when you run the amp hard into a larger load than it is set/intended for. The reflected Z on the primary becomes incorrect and mismatched as well. The energy/spikes created by the output tubes needs to go somewhere, and if it can't be absorbed by the intended load, it *will* go somewhere. So either it arcs a tube socket or it shorts adjacent turns on the primary out the output transformer. In extreme cases the primary burns open....

<<<"too high primary z caused my opt death" is what you said.

yes, i said i was dubious about that failure mode--one which you are promoting as widespread.

i'm dubious about that hypothesis, because 1) i've never seen it first hand and 2) many years ago an esteemed member of this board (and personal friend) did a series of tests on various methods of controlling this nefarious "flyback voltage" and the result was that it was not quite the demon it was made out to be. this was with an absolute WORST case scenario: a completely open secondary.

clearly a 4x mismatch on the secondary is but a fraction of that severity.

if you want to caution people about the dangers of a mismatched secondary load, be my guest. i will continue to claim that the dangers have been historically overblown, and i have evidence beyond a single (and circumstantial) occurrence to support it.