Dirk Offringa wrote:
If you believe I need more information to get me there, and you believe you have that information, why don't you share it?
I tried. You chose to ignore it. You are convinced that there is a problem with V5, yet you have done nothing to convince me that there is. When you did your last little experiment of jumpering from the effects out to the power amp in, you claimed that proved that V5 was the problem. Really? Did you forget about the fact that you also removed V9 AND V10
from the signal path as well as every other component in the reverb circuit? Obviously not, since you concluded that V5 was the problem. Then you tried to swap tubes in V5, V9, and V10 and every one of them apparently physically/electrically failed or failed to do what you wanted them to do. You must have very bad luck to have gotten three brand new, yet bad tubes. But you are still convinced that V5 is the problem.
Let me ask you a few questions:
1. Have you replaced ALL
of the tubes like was suggested? You bought the amp used. It is several years old, and you admitted that you had no idea what condition the tubes were in. Seems like that would be a good thing to do to me.
2. Did you try and at least clean the pins and sockets of each tube and reseat them as another poster suggested?
3. Did you bias the power tubes PROPERLY
as I suggested? You would be amazed as to the difference in the sound of an amp that that little adjustment can make.
4. Have you measured the power supply voltages and the voltages at each of the tubes to make sure that there isn't a problem with very low or very high voltages that is affecting a tubes performance?
5. Have you used an oscilloscope to trace the signal through the amp to see what it is actually doing in each amp stage and where any gain problems might actually be, if indeed there are any problems?
6. Have you done ANYTHING
to determine what the actual gain is through the part of the circuit that you are convinced in the problem?
Somehow I doubt you have done anything that has been suggested or thought through the amp circuits and how those circuits might affect the amps performance. No, you have a marked up schematic and a list of mods to make and you are convinced that V5 is the problem. So go ahead. Make all those mods. I would be very interested in how they all turn out and if you are able to turn your amp into the fire breathing but quiet amp you think it should be by doing those mods, I will gladly apologize.
Oh, and one other question. This forum is visited regularly by several people who know more about amps than you will ever know. In fact, they know more about them then I do. Have you stopped and asked yourself why after reading your thread (notice how many people have visited your thread compared to the number that have actually posted in it) none of those people have taken the time to try and help? Could it be because it is obvious that you have ignored everything that has been suggested to you and are convinced that V5 and only V5 is the problem? Think about it.
I don't need to know anything about you, where you live, what your situation is, or anything else to help you troubleshoot your amp. But you need to have some understanding about how the amp operates and what the impacts might be of the changes you are considering making. You need to learn to LISTEN
. If you are willing to do that and try and understand what you are doing, I'll be glad to try and help you. Maybe some of the others will too. But if you are going to blow off what people are saying, then by all means, go ahead and make those mods. You're on you own.
What's it going to be?