The great Tung-Sol tube failure mystery

[DrNomis_44]

Yes, have been having a conversation with Evatco. No mention of the Tung-Sols potentially being faulty. Check out the amp, etc...
The amp's performing like a trooper with Tube depot 7025's and NOS Mullards, so I'll just leave as-is for now.
When the cause is eventually determined, I'll share accordingly...

Just a thought, has the amp ever been in transit recently?, ie, being transported from one place or another?, also, was the amp recently moved from a warm environment to a cold one after it had been powered down after use?, that can sometimes end in tubes cracking.

[RalphH]

Just a thought, has the amp ever been in transit recently?, ie, being transported from one place or another?, also, was the amp recently moved from a warm environment to a cold one after it had been powered down after use?, that can sometimes end in tubes cracking.

None of that... been in my music room for 18 months. Average temp 16-25° over 12 months winter-summer. Just popped the lid and stuck the Tung-Sols in. Finished a 2 hour session last night with the old 7025's installed without a problem. Hmm...