Steve Deckert
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It's OK Scott, keep rattling... ; )
BTW, Interesting tidbit about your amp and the art of trouble-shooting mysterious problems:
I got your TORII MK4 that I just did anniversary mods on back with the dead channel, and had two extreme mind-melting hours trying to figure out the impossible...
After doing the 25th Anniversary Mods and testing the amp all the way through, which is my preferred methodology, I got down to the final mod, the glass resistors. So simple, just remove existing resistor and replace with new one, do it 6 times. I finished one channel and tested it, and then finished the other channel and "thought I tested it" but actually didn't. So based on the certainly aka assumption that I had tested that final resistor, I was unable to find why the hell the amplifier did not work on one channel. It worked, but the output was so low it was almost undetectable. Every part in the amplifier tested perfect, all resistors, all capacitors, and on the scope, the input stage all the way up to the output tubes was working perfectly, but the output tubes were not passing the signal on to the output transformer... yet, the tubes were clearly working, in fact they were drawing 50% more power than they should have, which is also btw impossible. Output transformer tests perfect, yet just to be sure that what tests perfect actually is perfect, a new one is swapped in and no change... Based on everything I tested, and everything I think I know, what is happening is completely impossible, and really starting to piss me off...
Then I remembered, troubleshooting anything, no matter how complicated, is not you pitted against the faltering item, but rather you pitted against your own mind. It is nothing else but that. The actual problem with anything is always something simple, or if Father Murphy wants to really punish you it will be three very simple things all at once. My mind was operating under a false pretense which was that I personally tested and witnessed both channels working perfectly after doing the all of the Anniversary mods on this amp.
So now that you have all the pieces to this puzzle, can you figure out what was wrong with the amp? How can a channel that is not oscillating and has no output yet is drawing 50% more power causing 31 volts to disappear not working properly when all the parts are there, and test perfectly?
One of the parts was soldered to the wrong place. Pin 6 instead of pin 5. Yes, it's a good one... one of Father Murphy's favorites... (He is such an asshole I can't even believe it. Did you know Father Murphy has a hidden camera to record his pranks and they play this shit back in the heavens like the show that used to be called "Candid Camera" ? Well it's true. Then they make you watch it during a life review after you die, just to have another good laugh!
Anyway, as far as I know it's a first for me, a sign of getting older I guess, nevertheless I did what I could to make it right, which was to fix it the day it came in, and cover the shipping both ways since it was my mistake ; )
BTW, Your very pretty ZTPRE came out great, as they all do, but I took an extra day to enjoy yours in the listening room so it has around 55 hours on it and is sure to please : )
-Steve
P.S. When I say "it was a first for me" I do not mean my first mistake!!! I have repaired mistakes and paid shipping both ways enough times over 20 years to easily pay cash for a nice new home, but as you can see the karma that came from it is worth far more than the money that would have been saved by skirting the responsibility : )
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