LV
Boom
This sort of thing regularly happens to the PSU inside a BBC B. You get a hissy pop sound, oodles of smoke and a niff like marmite on toast being cremated. Dramatic, certainly, in the case of a Beeb, but not all that noteworthy. In fact, I don't even switch the Beeb off any more when the PSU goes pop, because it still works for about another 10 years or so as if nothing has exploded at all.
However, in the case of the Domesday Player, I thought it best to switch off, so I did, within a nano-second.
To my not inconsiderable relief, I found that no lasting damage appeared to have been caused to my good VP415. It was still working after I switched it on again, at least for time being, for things were to get very much worse.