Xlch721 Posted September 4, 2008 Share Posted September 4, 2008 I bought my Valve Junior about a month ago. After a couple of weeks I decided to swap out the tubes with a JJ El84 and a Tung-Sol 12AX7.Well tonight I turn on my amp let it warm up for a couple of minutes and start jamming. Next to my suprise my amp starts buzzing like crazy and making all kinds of noise so I unplugged it. I waited about a half hour or so took the back panel off fired up the amp and my power tube does not light up now. I bought the tubes from The Tube Store on 8/15 put them in on 8/21. I noticed when remove the JJ that several pieces of copper above three of the pins are broken and there is a small crack in the glass about an 1/8th of an inch long . The inside of the tube was arcing like crazy when I pulled the plug on the amp and it smelled nasty. I took the amp apart and looked for burnt components, traces ect everything looks good so I put it back together with the stock El84 it works fine now. I am just curious as to why the tube went bad so quickly I only had about 5 hours of playing time on it. Been so busy at work that I have not even really had a chance to use the thing. I know that I plan on contacting The Tube Store in the morning to see if they will replace it. I have been running tube amps since 1977 when I was six years old and have never seen a tube go out this fast or arc like this one did. Link to comment Share on other sites More sharing options...
layboomo Posted September 4, 2008 Share Posted September 4, 2008 I bought my Valve Junior about a month ago. After a couple of weeks I decided to swap out the tubes with a JJ El84 and a Tung-Sol 12AX7.Well tonight I turn on my amp let it warm up for a couple of minutes and start jamming. Next to my suprise my amp starts buzzing like crazy and making all kinds of noise so I unplugged it. I waited about a half hour or so took the back panel off fired up the amp and my power tube does not light up now. I bought the tubes from The Tube Store on 8/15 put them in on 8/21. I noticed when remove the JJ that several pieces of copper above three of the pins are broken and there is a small crack in the glass about an 1/8th of an inch long . The inside of the tube was arcing like crazy when I pulled the plug on the amp and it smelled nasty. I took the amp apart and looked for burnt components' date=' traces ect everything looks good so I put it back together with the stock El84 it works fine now. I am just curious as to why the tube went bad so quickly I only had about 5 hours of playing time on it. Been so busy at work that I have not even really had a chance to use the thing. I know that I plan on contacting The Tube Store in the morning to see if they will replace it. I have been running tube amps since 1977 when I was six years old and have never seen a tube go out this fast or arc like this one did.[/quote'] Either a defective tube or you cracked it or f#cked up a pin insalling the tube....it's easy to do and one of the down sides to the valve jr is not being able to see the tube sockets very easilyIMO. Link to comment Share on other sites More sharing options...
cGil Posted September 4, 2008 Share Posted September 4, 2008 Yep. Bad tubes can happen at any time, even to FOB tubes (Fresh Out of the Box). They usually die at the worst possible time, so always keep spare tubes handy, especially in your gig bag. After all, you'd keep spare light bulbs for your crib, right? Gil... Link to comment Share on other sites More sharing options...
Billy Hell Posted September 5, 2008 Share Posted September 5, 2008 I think I'm in the same boat with the same tube combo. You really seem to have to push to seat. I'm doing tube swaps this morning to verify it's a tube. Link to comment Share on other sites More sharing options...
Xlch721 Posted September 5, 2008 Author Share Posted September 5, 2008 I think I'm in the same boat with the same tube combo. You really seem to have to push to seat. I'm doing tube swaps this morning to verify it's a tube. How did the tube swap work out? I am running a Sovtek for now because that is all I have and the local shops don't carry much in the way of tubes. I did order a pair of JJs though should have them by the middle of next week. Link to comment Share on other sites More sharing options...
TommyRocket49 Posted September 6, 2008 Share Posted September 6, 2008 I heard/read that NOS Tesla'(not JJ) EL84's are the DEAL; along with TungSol 12AX7's Did anyone achieve a running set-up yet? Link to comment Share on other sites More sharing options...
gmm20 Posted September 6, 2008 Share Posted September 6, 2008 If you saw the tube arc, then maybe the tube lost it's vacuum seal. I suppose it could happen, but I don't get my tubes from anywhere else but from Fat Willy out of Denver. -g Link to comment Share on other sites More sharing options...
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