Western Electric 300B problem


So I recently purchased pair of WE300B, Friday night first listen. At start up heard mechanical pinging and popping, pre muted so nothing through speakers, after the pinging and popping ended, pre out of mute heard nothing unusual through speakers. No issues other than blue glow at tops of tube throughout 5 hour listening session. Tonight I power up tubes for second listen, immediately see left monoblock tube goes completely cloudy with blue fog throughout tube, this along with popping, right monoblock tube fine.

 

So it seems I have gassy tube, lost vacuum already! And here I thought recent improvements with quality control there had solved these issues. Not happy with this purchase, been running Psvane Acme 300B's for nearly 1000 hours with no issues.

sns

In regards Upscale, just received my Return Authorization. I explained symptoms and sent photo, they agree tube defective.

Discovered my GZ34 rectifier tube was trashed. So, is this amazing coincidence rectifier tube decides to fail just after replacing 300B tubes or did failing WE take out rectifier tube?

 

Too bad, these early 50's Mullard GZ34, probably around 700 hours on them. Hope I can find some nice replacements. I guess it could be much worse, damage to amp.

Paid $300 for 1958 NOS Mullard. These continue to rise in price, forgot what I paid for original pair, wasn't cheap. Feeling lucky to get away with this, fearful I had taken out components in amp.