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At the other end of the two resistors connected to the anodes - ie pins 1 and 6. In theory, you should also get the same voltage on both, but at this point we assume nothing.

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Great tones come in small glass jars!

Interesting. I get 235v there. For shits and giggles I measured pin 1 and pin 6 again because since my last measurement I had touched up some wiring and swapped out all my NOS tubes (except the rec) for the EH and JJ ones that came with the kit.

I now get 118v on Pin 1 and 117v on Pin 6, totalling 235v.

I also tried to pull each V3 and V4 separately to see if for whatever reason I could tell a difference. Both power tubes in and either power tube out all sound exactly the same.

Those voltages look good now. It also looks like you've fixed a fault here, but there's something else badly wrong in the amp. Now it's time to do some methodical fault diagnosis, using a simple signal injector probe. Basically it's a signal cap of any value between 0.01uF to 0.68uF (400V or higher) soldered onto a an iPod/Walkman type earphone cord. Also solder a crocodile clip onto the shielded side of the headphone wire. Then you clip the shield side to ground and *carefully* touch the free wire coming from the cap to the grids of each of the following stages. You can also remove the 12AY7 in the first position for this test, so that it no longer interferes with your tests of the following stages. That should give some clues as to where the signal is getting messed up. Obviously, the signal will sound less loud as you work back towards the power amp stage. *** BE CAREFUL WITH LETHAL HIGH VOLTAGES. KEEP ONE HAND IN YOUR POCKET WHILE DOING THIS TEST. ***

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Great tones come in small glass jars!

I've got say. This one has me worried. Is there anyway I can accomplish something similar without creating this makeshift device? Any pics of what this will look like? I feel uneasy making assumptions on this one. I've always been a big fan of living.

I grasp that one end of the cable will have the live wire going through the cap to touch the circuit and the shield to ground, but what am I doing with the other end? Plugging it into something that will make a sound so that it will go through the amp and I can tell where the output falls apart?

The other end plugs into a Walkman, iPod, MP3 player etc. Then you crank up the volume. I'm assuming you don't have a signal generator - so this is a substitute. If you like you can tape the cap onto a chopstick, so that the free lead at the end of the cap sticks out beyond the end of the chopstick. That should help you feel safer.

Another approach is you can remove the jack from one end of a guitar cord, and solder a 400V (or above) signal cap onto the centre core, and attach a croc clip to the shield side. Again you can strap the cap onto a chopstick. Then plug the other end into a different amp, and go through your sick amp, listening to the signal at each grid. That will also tell you where things are going wrong. Then it's a case of chop-sticking wires and reflowing solder joints. Also if you're using any carbon comp resistors, be aware of the possibility of the carbon rod inside cracking. So you may also want to measure the resistor values in the general vicinity.

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Great tones come in small glass jars!

Thanks Zaphod, I don't want you to think I'm not appreciating your advice. You've been a great help in helping me troubleshoot this issue and in learning more about amp repair. It's just that I want to have a full afternoon and lots of focus when I do that next step, because of my lack of experience and the risks involved. It's looking more and more like I won't get the chunk of time I need to do that until my vacation starts in two weeks.

Thanks for all the help, please give any other ideas guys, but this thread will probably be dormant for about two weeks and as soon as I can work backwards with a signal generator, I'll post the results and be back with my hand out looking for advice again.

Thanks guys.

James aka LowWatt

That's OK I can take the hint.

So you do have signal generator then? If so, you can forget about the iPod with a cap thing....

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Great tones come in small glass jars!

Actually quite the opposite. You've been working so quickly to get me answers and I knew it'd be a few weeks until I would have the time to build a makeshift signal generator and do all the necessary testing. I just didn't want you to think I was ignoring your speedy advice or that it was going unappreciated. I just won't have time to take you up on it for a few weeks.

It was the Output Transformer!!! Thanks for all the help guys, but I ended up cheating and taking it to Tim at Superfuzz Audio.

How much did Superfuzz charge you, just of interest?

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Great tones come in small glass jars!

$25 on the diagnosis and turned it around within a few hours of me dropping it off. Considering how tight my time has been lately, I'm pretty happy with those figures.

I've already got the replacement on the way and hope to have my Deluxe back to life by the end of the week. Since that it wasn't a situation of abuse or misuse, Stephen replaced the OT for just the cost of shipping and had it turned around immediately for me.

Now once I get this back to life, it's time to start looking at a KT66 Triwatt for the loud and cleans.

The Deluxe is back and working beautifully. Thanks for all the help guys. Sorry to cheat and get the OT diagnosed by a tech, but time has been impossible to find lately.

I just put this note at the top of this thread.

PROBLEM NOW SOLVED. THIS THREAD IS STAYING UP TO HELP OTHERS. In the end, Stephen saved the day and got me my replacement Output transformer fast and for only the cost of shipping it to me. Swapped the tranny and everything was back to perfect. Thanks Trinity!

$25 sounds very reasonable to me. So does the price of that replacement OT.

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Great tones come in small glass jars!

Hey Lowatt,
when you had this issue was it intermittent? I think my amp may have the same problem if so. I was at a jam the other day and about 2 hours in to the jam iI had a huge volume drop, I checked all inputs and had the same issue. so i turned the amp off and ran through the pa for a while. later on i plugged in a gain and it worked fine for about 20 mins then the volume dropped again. I am trying to get it to do it one more time so I can trouble shoot.

It was not intermittent at all. It was perfect, then unusually quiet. After it had gone quiet, it never came back to full volume until I replaced the Output transformer. The amp has been 100% since.

Let us know what happens if you can make it happen again.

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Update I had this happen again the other day while i was at L&M, I thought it might be and issue with the power tubes so i swapped them out but still having the same issue (although the volume drop doesn't seem as low as the first time) seems to have droped the volume by half atleast. When i got it home it was still quite so I took some messurements with my volt meter and every thing seemed to be fine (i will post numbers tonight) I evern tried it into another cab to see if the speakers was going, but got the same results. I think i am going to go through and re-flow the solider joints incase I had a cold solider joint.

We can send you an OT and you can try it. If it solves the problem, just cover the shipping. If not, ship it back.

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

I might take you up on that, I want to check one more thing this weekend, as I realized that I only had this issue after chaging the Rectifer. so I am going to put the old one back in, If it fixes it I will be very happy.

UPDATE:

I got the new OT a few weeks ago and it worked like a chram thanks for the Help.