What happened after your miswire insident? |
The problem is that I rewired the power inlets (the ones without the fuse holder) and I'm pretty sure I mis-wired one of those, somehow, as I was damn careful. I was also under the illusion that they carried AC. My stupidity. The variac wiring seems straightforward and I'm almost certain that it is correct. Voltage appears normal on both amps but on the right amp, the power tubes don't light. On the left amp, they light too brightly when bringing up the voltage. This condition follows the amp if I reverse left to right. Anotherwards, the power cords don't seem to make a difference.
And after careful measurements with an ohm meter I made the wires match what the ohm meter would suggest is the same, banking on the amps are wired as mirror images. Thought I was on to something as it was so logical.. Now I have no voltages showing on either meters and no power to either amps power tubes. I pretty much "cooked my goose". |
You may want to try to post on the OTL asylum at audioasylum.com. Those guys seem to know a lot. Wonderful amps. Sorry you are having a problem. |
Hi Desalvo55 you should contact Rich Brkick at Signature Sound, a very nice person, he works on Joule and might be willing to guide you!!!!
Sam |
Before doing anything else, I would call Jud on the phone. |
Send me the internal photographs. If you find someone with 'untouched' amps ask them to send photographs too.
Your photos can be handy even if you refer to manufacturer that more likely would ask you to send both units.
Does that mean you were changing captive poercords?? |
The fact that you said one ran to bright and the other was not lit at all is probably because the bright one was getting 2x the power, as the other wasn't pulling any at all, sound plausible?.
Now that you have not power to the power tubes have you checked your fuses? Hopefully they are blown and they have protected your amps and no other damage was done. If you post a link to photos of your work I'll compare them to my amps for you. |
Hey guys thanks for the posts.
I brought this on myself by wanting to rid the amps of those cheesy power cords. Simple enough but it wasn't. I didn't take any pictures like a total idiot. I assumed they were wired identically like an idiot. They are not. I measured all points with an ohm meter so that the amps measured the same. Bingo. NOT. Now neither one of them work.
I brought them over to Nick Gowan of Truesound, a tube amp guru repairman. He took a look and was in what I would term as dismay. "Reminds me of the old Audio Note amps". I think he has doubts whether he can get these working without any pics or documentation. They look like they were built in a garage. I think they were!
I've taken pics and sent them to Jud's repairman but he referred me back to Jud who simply told me to put the old cords back in. Followup emails have been ignored.
If Nick and I even knew they were to be wired in a similar fashion, that would be extremely useful.
Checked and ohmed the fuses. Checked the bridge rectifier. Checked everything I could check. Nothing looks broken other than some bulging caps. A simple (not so simple)miswire with no roadmap.
I agree with Johnthompson regarding full power to one amp. I'll try to upload pics to Flicker to post link.
Appreciate the help!
Pretty worried at this juncture. |
Got it sorted out myself. In the end, I really could find a mistake in wiring. I just trimmed and reset all the connections. But something happened. There's no hum anywhere and the amps sound even more amazing.
Thanks again for your help. |
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Desalvo55, the tube sockets in that amp overheat as they were never intended to handle the filament currents that a 6C33 requires. So the filament connections tend to develop bad connections after a while. If the socket is not too far gone the filament connections (the 4 opposite the large pin) can be retightened and you will be good to go for a while.
Eventually though the socket will fail and should be replaced. This will be evident as tightening the filament pins will not seem to last so long before the tube won't light up properly again.
The Russians spec'ed the socket to be replaced every time the tube is replaced, as they primarily used the tube for military purposes. So when that tube first made it into this country (BTW we were the first US manufacturer to use them in a product) the socket was shipped with the tube.
In consumer gear though there is an expectation that the socket will last longer than that and they do. But you should be aware that they do have a service life that is measured in 1000s of hours rather than in years or decades like most tube sockets. Realistically I think you can get about 10,000 hours out of them- that will vary depending on how hot the amp is actually getting.
(FWIW it was this tube socket thing that convinced us to stay with the tubes that we use in our OTLs.) |
Wow, that is really great information.
I got no help, no love from Jud. But many fellow audio guys have really come to my rescue. When something breaks (or I break something) in my house, in about 1 day someone has a spare for me to use till I'm up and running. The wife is really impressed by us audio guys.
It's really cool to be a part of something that so many share a passion in and, generally have a really good core.
I think "reboot" was the answer. |
" think "reboot" was the answer"
I believe this is what Jud wrote to you when you suggested to restore old wiring...
Its not in his habbit to write long e-mails.
You love you amp ? Enjoy it and thanks designer.
Next time before you will wish to "improve" and to "mod" compex engineering stuff - you will give it to qualified hands and may be, just may be consult designer before hand.
I am glad that it ended well! Congratulations, we all know these tortures with "new and improve" stuff
Rafael |
As Dob suggests, I don't believe many manufacturers would be willing and happy to assist with non-factory modifications to their products. In that regard I don't think anyone can fault Joule (Jud) for suggesting anything other that a return (reboot) to the stock configuration.
I'm not saying none of us should never attempt to improve on a factory stock design. But if we do, how fair is it then to expect warranty coverage (not the case here) or hand holding if something goes wrong? |
