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Post by techboy on Apr 18, 2016 10:10:37 GMT
Since getting 6sn7 tubes, Sylvania 6sn7wgt works fine But. Tried 3 VT 231's. Two from Syl. One from RCA. All 3 have a severe buzzing noise. Increases with use. Could it be a grounding issue? Or could it be the adapter? 12AU7 work fine. As do 6dj8. As do Syl 6sn7wgt. Please help. Not usable with VT 231 tubes so far.
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Rabbit
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Post by Rabbit on Apr 18, 2016 11:05:37 GMT
Are VT231 tubes supposed to work in an Ember?
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Post by techboy on Apr 18, 2016 11:10:49 GMT
Are VT231 tubes supposed to work in an Ember? Yes. VT 231 = 1940's Mil variant of 6sn7 People are using it fine. Note: using almun foil over the tube -> reduces noise putting on top of DAD -> reduces the noise bypassing input capacitors -> increases the noise removing 25ft extender cable -> reduces the noise
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howie
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Post by howie on Apr 18, 2016 13:25:16 GMT
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Rabbit
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Post by Rabbit on Apr 18, 2016 14:05:57 GMT
I had a buzz with my first Sunrise. I found moving it around made the buzz become worse or better depending on where I left it. Try changing position. Also, try earthing with a little piece of wire wrapped around the back of the volume pot and connect the other end.... I think it was to the frame.
If it's not consistent with different valves, it looks more to me like it could be the valves themselves. If an amp buzzes, it would normally do it with all valves to a greater or lesser extent, depending on the valve and gain.
I know this sounds daft, but just try putting tin foil over the amp and hold onto it to see if the buzz goes. If it's airborne, then the foil might knock it on the head so that at least you know whether it's coming from something else.
I hope the computer power supply is well away from the amp power supply. Check that the power supply is on its own.
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Post by jhelms on Apr 18, 2016 15:17:23 GMT
As I mentioned in the email you sent, if you can use a 6sn7 just fine as well as other tubes but your VT231's you bought are not working, then that would be the tube. We have used and have a lot of customers using vt231's without issue (including myself). As noted, just a mil-labled version of a 6sn7. Could be in their individual designs, could be they are very very used and test poorly / way out of spec. Could be a lot of things. And saying they work in another no name amp really does not say anything at all because likely that amplifier is not designed electrically even similar to your Ember.
As Ian mentioned with the foil trick, those particular 231's may be highly susceptible to noise in their design or again, they can be so used up / test so poor that they are just not capable of running in your Ember.
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solderdude
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measureutternutter
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Post by solderdude on Apr 18, 2016 16:35:26 GMT
Some tubes still work in high voltage all tube amps butr are too 'worn' to operate on the relative low voltage of the Ember.
If you can't get it to work with your amp sell the tubes and use the ones that DO work.
Or you but a metal can around it and electrically connect that to either: 1: The left rear 'post' of the amplifier but you MUST jumper wire 'OPT-1' for this to work 2: The metal part of the volume control 3: The screen of one of the RCA outputs.
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Post by techboy on Apr 18, 2016 17:50:56 GMT
As I mentioned in the email you sent, if you can use a 6sn7 just fine as well as other tubes but your VT231's you bought are not working, then that would be the tube. We have used and have a lot of customers using vt231's without issue (including myself). As noted, just a mil-labled version of a 6sn7. Could be in their individual designs, could be they are very very used and test poorly / way out of spec. Could be a lot of things. And saying they work in another no name amp really does not say anything at all because likely that amplifier is not designed electrically even similar to your Ember. As Ian mentioned with the foil trick, those particular 231's may be highly susceptible to noise in their design or again, they can be so used up / test so poor that they are just not capable of running in your Ember. These are NOS unused tubes. 2 of them bought from big name dealers and not Ebay!
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Post by techboy on Apr 18, 2016 17:51:32 GMT
Some tubes still work in high voltage all tube amps butr are too 'worn' to operate on the relative low voltage of the Ember. If you can't get it to work with your amp sell the tubes and use the ones that DO work. Or you but a metal can around it and electrically connect that to either: 1: The left rear 'post' of the amplifier but you MUST jumper wire 'OPT-1' for this to work 2: The metal part of the volume control 3: The screen of one of the RCA outputs. How do I do 1 or 2 or 3? please elaborate.
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Post by techboy on Apr 18, 2016 17:52:42 GMT
How can I solve grounding issues?
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Post by techboy on Apr 18, 2016 19:20:53 GMT
The buzzing is there even when Ember isn't connected to the DAC.
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Rabbit
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Post by Rabbit on Apr 18, 2016 19:59:11 GMT
Personally, I wouldn't use those tubes. Change to a quieter one.
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Post by techboy on Apr 18, 2016 20:22:06 GMT
Personally, I wouldn't use those tubes. Change to a quieter one. That would mean not using any 6SN7 tubes!
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howie
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Post by howie on Apr 18, 2016 20:41:43 GMT
Personally, I wouldn't use those tubes. Change to a quieter one. That would mean not using any 6SN7 tubes! You said at the beginning that your Sylvania 6SN7wgt worked fine.
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jello
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Post by jello on Apr 18, 2016 20:42:12 GMT
Right now that doesn't seem like a bad thing tbh. I guess it depends how much time and effort you want to devote to troubleshooting.
Have you tried turning it off and back on again?
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