Posted by SteveBrown [ 68.0.84.71 ] on December 16, 2007 at 08:19:52:
In Reply to: Scott 299C and 7591 tubes posted by theo on November 18, 2007 at 11:08:07:
I have heard that new manufactured tubes may have slightly smaller pins than the original. That, combined with old, dirty and worn sockets, may be all that's wrong. I assume when you got the loud POP, it wasn't a Bang (cap going out), nor did you smell smoke. Right? If so, I'd bet it's just the pins. By the way, check your tube plates and make sure they're not red or glowing. Personally, I'd get an old amp like that checked out. As I recall, this amp used DC from the front end filament supply to also provide fixed bias on the outputs. Good chance you need to replace the low voltage rectifier and the power supply caps. A good tech can tell you for sure. In the mean time, don't leave it unattended while running... 
[ Tubes Forum ] [ Help ]