No.4 Posted April 24, 2017 Share Posted April 24, 2017 I posted this question on the diytube forum but I don't know how much traffic there is there anymore, so I thought I would see if anyone here had any insight or any similar experiences. The amp is a diytube Clementine using kt88 tubes. I have used this amp daily for over two years with no issues at all until now. Any advice is appreciated during this sad time. Last night I noticed a strange noise from one channel while I let the amp heat up with the source off. Every 20 or 30 seconds give or take the left channel would make a muffled sound for a second or two. The sound is like a muffled pop followed by a faint feed back sound. I was hoping the sound was being caused by a tube failing but now I don't think so. I swapped the tubes this morning in hopes the sound would follow it but I didnt. The sound actually got much louder. I shut the amp down after the first pop because it was much louder in comparison. The left channel socket feels looser than the right so I am a little suspicious of that. Has anyone experienced anything similar? Any advice where to start? Quote Link to comment Share on other sites More sharing options...
NOSValves Posted April 24, 2017 Share Posted April 24, 2017 Look down into that loose socket and determine how the metal contacts inside grab the tube pins, tighten it up so it grabs the tube pins firmly. A dental pick type tool works best for this. Quote Link to comment Share on other sites More sharing options...
No.4 Posted April 24, 2017 Author Share Posted April 24, 2017 The more I think about it the more suspicious I am of the socket. I think some of the noises corresponded with vibration in the environment. When I stomp my foot some of the times it would be audible. When I switched the tubes this morning the amp was silent until I stomped my foot; a few seconds later was when the noise crept up louder than before. Quote Link to comment Share on other sites More sharing options...
HDBRbuilder Posted April 24, 2017 Share Posted April 24, 2017 Quit stomping your feet so much. 1 Quote Link to comment Share on other sites More sharing options...
No.4 Posted April 24, 2017 Author Share Posted April 24, 2017 1 hour ago, HDBRbuilder said: Quit stomping your feet so much. But it is the first step in trouble shooting any problem. Quote Link to comment Share on other sites More sharing options...
NOSValves Posted April 26, 2017 Share Posted April 26, 2017 It could easily be a cold solder joint any where in that channel. Quote Link to comment Share on other sites More sharing options...
No.4 Posted April 26, 2017 Author Share Posted April 26, 2017 Not to jinx myself but I cleaned the tube sockets with some deoxit and "resprung" the contacts on Monday and the channel has been dead silent since. I have used the amp twice so hopefully this has resolved the issue. Although this is a diy amp I am very confident of my soldering and mechanical connections. Though I may check the tube socket joints to see if there has been any change with heat cycling. Thanks for the suggestions, hopefully this will not pop up again. Quote Link to comment Share on other sites More sharing options...
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