Hi again gang,
It feel quite supported after reading all of your most recent posts. Thank you. It sure helps.
To answer a couple actual and potential questions here, the fuse looked perfect when I checked it immediately upon the noisy shutdown I have described. It looked intact, centered, and clean. Also, the noise that occurred with the event did not come from the amp's direction; it came from the speakers. This indicates to me, in general, that indeed the cause was in the signal path, and not just in the amp's power supply path. But then, I do not know what circuits have common components.
The recent work was not done in a formal company lab. It was done privately at the home of a highly recommended tech manager for ElectroHarmonix/Sovtek. He claims to have a personal warranty he adheres to. I do not know its terms. I know this though, that his professional reputation could be put on the line if I were to call ElectroHarmonix and they thought I had legitimate complaint. He would be out of business at the private level, and could lose his good career at ElectroHarmonix. I doubt he meant mischief, but I have strongly suggested to him that he give me back some money.
Yes, the amp sounded quite different during the two or less minutes that it did work before it shutdown. The guy who replaced the tubes told me he was getting a lot more power without distortion. I think he may have been correct on that. I actually felt that I could take the rig and play a venue with no PA and do okay, for a refreshing change! But I made no conclusions; too early. At the same time, I preliminarily noted this following, something about the new power remotely impressed upon me the idea that this difference was a bit much for the rig to handle without a problem. I can't describe this impression any further. And then...snap crackle pop.
The tubes he put in were made by his company --no problem in that. And for goodness sakes I figured that if anybody knows tubes it would be him! Exactly what he put in were the following. He replaced the 12 existing power tubes (I forget the name; they were 6L6's and had a brand logo that amounted to a C with a circle around it) with Svetlana SV6L6GC tubes with an IP of 44, and a GM of 5,200, whatever that is. These are structurally different than the 6L6's that were in there, at least insofar as the new ones' internal parts (anode, etc.) are mounted in the tubes with little springs at top AND at the bottom inside the tubes) to reduce the tendency of the working parts of the tubes to vibrate from ambient sound vibrations in the room, and thereby reducing the tendency for the tubes themselves to make a distorted sound (a phenomena called microphonics). Additionally, he replaced only the first preamp tube that the signal reaches in the head. He put in a Sovtek 5751. This tube apparently does a superior job at cleaning up the incoming signal. So it too was meant to be an anti-distortion measure.
locutusofborg10, yes please give me the number for Jeff Bloch's in Brooklyn. I want it as a resource for the future, certainly. However, if I get my mind and available cash together here, I will no doubt just send the amp across the country to Mesa, this time. They too are trying to help me, as are all you good people, and of course as are the Wickershams.
I will not give up, although I have very seriously considered it. It seems that we who do play, must play, lest our angst grow to monstrous size. Thank you all again. And let's pick up with this issue later when there exists more content to discuss. I will write at that time. Hope you will still be tuned in then. That is, unless anybody has more for me right now....
Happy Holidays!
Turk
