Well, my matched octet of EL84 tubes arrived today. The first thing I did with them is run them through my Jackson 658A tester. On initial testing, everything tested well except that on 4 of the 8 tubes, there was flashing on shorts test K (the first shorts test).
After finishing the initial test, I decided to retest the 4 failing tubes being sure to give them plenty of time to warm up. The first 2 tubes I tried then passed shorts test K with no problem. The third tube still has a flashing problem with this test. The last tube arced when I inserted it into the tester. By arced I mean that there is an extremely bright, flashing, white light.
To be sure that my tester wasn't the problem, I reinserted a tube that originally passed shorts test K. It exhibited normal behavior including still passing test K.
So I have 1 defective for sure and 3 other suspect tubes. I sent a message to the seller asking him to suggest a resolution to this problem. We'll see what he says. Do you think that I should insist on all 4 (potentially) bad tubes being replaced or just the one that arced?
I guess I need to see if JJ EL84 have a reputation for being "fragile". At least it happened in my tester and not my amp.