How to detect tube arcing?
fredv
Posts: 923
I saw this terms many many times but couldn't figure out how to detect such happenning in the tubes. I need some education, please.
-fredv-
Post edited by fredv on
Comments
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Lick it. If your sizzles, you've done something wrong.
Disclaimer: This is a joke, not serious, do not try this...
BTW, I have no idea unless it looks like a lightening show.There is no genuine justice in any scheme of feeding and coddling the loafer whose only ponderable energies are devoted wholly to reproduction. Nine-tenths of the rights he bellows for are really privileges and he does nothing to deserve them. We not only acquired a vast population of morons, we have inculcated all morons, old or young, with the doctrine that the decent and industrious people of the country are bound to support them for all time.-Menkin -
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Look for flashes in the tube. Listen for nasty cracks in the audio.
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Yeah, what Mhardy said. Also, instead of flashes, sometimes you might see the tube get brighter and brighter until they go poof. I had a JJ 5AR4 arc in my ST-70 taking out the fuse.
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Interesting, I have a JJ 7591 behaved like that. Before it died, it flashed and killed the Sovtek 5AR4 along the way in my Eico ST-70. I shall take a close at it in a tube tester!!organ wrote:Yeah, what Mhardy said. Also, instead of flashes, sometimes you might see the tube get brighter and brighter until they go poof. I had a JJ 5AR4 arc in my ST-70 taking out the fuse.
-fredv- -
Keep an eye on it when you're testing. I'm staying away from JJ output tubes for now because they have some serious quality control issues. There are a lot of discussions regarding this on audioasylum.com
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That really sucks. Amongst all new production 7591, JJ sounds the best. In fact, I prefer JJ to the Westinghouse NOS 7591. I hope they will fix their ****. I kind of like their output tubes especially the E34L and KT77............organ wrote:Keep an eye on it when you're testing. I'm staying away from JJ output tubes for now because they have some serious quality control issues. There are a lot of discussions regarding this on audioasylum.com
-fredv- -
I don't think it's all of the JJ's. I have been using a quad of their EL84's for some time with no complaints, and I don't think I've seen anything on-line denigrating the EL84's in terms of QC. I think there were initial problems with the 7591's, which may be history now. I have a quad of these in a Scott LK-72 (brownface) but it has some preamp issues so I really cannot comment on them meself.
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The JJ 7591 went bad earlier this year. Since then, the remaining 3 and the replacement having been doing fine and providing nice tube melody in my bedroom. Quite frankly, I can't conclude it was the JJ's fault because the 5AR4 went bad at the same time, and this is the second bad Sovtek 5AR4 I experienced (died on a different ST-40). I just replaced my Svetlana EL34 (I believe they are very much like Sovtek from the New Sensor factory) with 2 new quad of E34L. There is absolutely no comparision to my ears!!! I hope the E34L will last ..........
-fredv-
