G Castles, thanks for the detailed info, I'll give that a try
"Just a possible answer" well John, you have jogged my memory. Last year I had an old Marshall JTM on the bench that under test would intermittently and quite suddenly cause one of the 34's to light up like a beacon before returning to fully working, it destroyed 2 new valves and I never got to bottom of the fault before giving it back. So it's quite possible the my Edicron was sacrificed in that amp, perhaps suffering the burnout while I was doing something else, me not realising what had happened?
