Once again, the risk of transformer failure from wildly careless drunk and clearly insane risk taking tube rollers raises its ugly head. I did an informal study of this issue a couple of years ago (this study is ongoing by the way) and determined...ahem...that NO TRANSFORMER FILAMENT HEATING RELATED FAILURE HAS EVER OCCURRED (or has been reported anywhere I've seen) from using 120s or now 150s (although it's early for these...be warned!) EVER in the history of the entire audio world. None. Zero. Also, Jolida techs have approved 150s (and previously 120s) for use in the 502p, I use them now (somehow the amp is surviving, although it could BLOW UP any second) after replacing 120s that got old, and, again, no issues for me or anybody else I've ever read about anywhere...in spite of warnings all over the place. It's possible it's happened, but data on those happenings is nil, nada, none, zilch...still I'd check with yo' mama before going outside, you might get wet.
