Well, you could send me back the 12BZ7 and I have a bunch of Westinghouse 12BZ7. It's too late for me to try and return the Raytheon, but I'll contact the seller just in case he's a nice guy. The 12BZ7 is ruining the experiment, because it's no good. It's one of those, "It tested good, but it's no good," tubes. It tested strong on my tube tester, but the tester can't test for microphonics. You have to stick them in an amp to see if they are okay. You did and it's a screamer, ringer and a real frickin' nightmare!
If I can get around to it, I will send you a Westinghouse 12BZ7. If it does the same thing, then we have solved that equation. If it kicks as, then we corrected our test pool of tubes.
Marty
