Good tube design is the main reason why tube(s) 'die piecefully' without affecting surrounding circuit components.
8 responses Add your response
" Any idea what would have made those two pre-amp tubes burn out silently? No pop or bang was ever heard-one day the phono chain was playing fine-next day zippo"
I can only join Marakanetz opinion that the answer lies in well thought design of the power supplies. My hat off to Jud Barber....but most of all for the pleasure his preamplifier ("300") gives me during listening to the MUSIC!!!!
Thanks guys, I think Marakanetz is on the right track and I trust his opinion after seeing his threads and replies for years here. Dob, have to agree about this pre-amp, its wonderful,better in almost every way from the Conrad Johnson I had before. Atmasphere, no theyre not lighting, just received two new tubes so will try them out today. All the other components work fine but when playing LP's, dead silence-no hiss, no pops, no crackles, nada. Hope its just the tubes, will see later today. Thanks again guys!
There are not many faults that can cause tubes to not light. In this case I bet the old tubes were also white inside.
If that is true, they lost their vacuum and its simply not possible that the preamp had anything to do with that, unless the sockets themselves are not quite correct for the 9-in noval spec. If the socket bends the tube pins slightly as the tube is inserted, and if you have Chinese tubes (which have glass that is not as rugged as NOS types) then you may experience tubes 'going to air'.