[Phil Allison]

"adchesney"

This is my first post (so go easy!) - I purchased a 300B amp off EBay
and I have really enjoyed it. Previously I built an Edison 30 amp.

However, the 300B has died, my daughter said the "middle bulb went
pop". This "bulb" she is referring to is the 274B tube.


** Went pop = the glass has broken ?????


My question is...how long should these valves last?


** How long is a piece of string .....


And what could cause premature failure.


** Tell us what failed.

The glass, the heater/cathode or has it arced internally ?

Tried a new valve yet - know if there is another failed part ?




......... Phil