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Is static the culprit?

Last year I sent my Odyssey Kismet amplifier in for repair because I was getting some intermittent  “static” noise either exclusively or at least primarily out of the right channel. This static noise was only audible (to me) when no music was playing and was loud enough to hear it across the room and even with only the amp and speakers connected it was still evident. 
Klaus was at first unable to replicate the noise but after awhile said that he could also hear it. I believe he said that he thought that perhaps a faulty capacitor was to blame and I decided to go ahead and upgrade the amp while he had it. Basically I have the latest and greatest as of about April of this year. 
Klaus was wonderful to work with and upon return it was now dead quiet and sounded simply incredible. 
However, It’s now doing it again and it occurred to me that when the weather is warm it seems to work perfectly but each time it was making this noise, it was colder weather both before repair and again now. This is going on my best recollection though so maybe it’s only just a coincidence? 
Could static have been the culprit all along? My main problem with that theory though is that I can’t understand why it would only be primarily out of only one channel. 
I can actually feel the static in the room and so I do think that any measures to reduce it would probably be in my best interest in any case. 
I’m I just crazy to think this or do you think that there may some merit to my theory? I’m not experiencing any “sparks” yet and so is there any chance that this noise could cause any damage or degradation to my system? It’s not really bothersome to me otherwise but if it could be troublesome then what can I do to minimize the static? 
My system: 

Odyssey Kismet amp
Chord Qutest DAC 
Bluesound Node 2i streamer 
Rel 5/SHO subwoofer 
Supratek Chardonnay tube preamp 
Ascend Sierra 2Ex speakers
Audioquest Niagara 1200 power conditioning 
various aftermarket cables (mostly Cullen and Audioquest)
speaker stands


My cables do cross each other more than I would like and are on my hardwood floor (not elevated) and I don’t really think that my tube preamp is to blame because I can still hear noise even with it completely off. I do cut the preamp off when not listening to music but I do leave everything else on. 
Thanks for any help! 





bacchus1234
atmasphere's avatar
atmasphere
11,793 posts
 
If temperature is involved this problem can be caused by noisy transistors in the input section of the amp. I've seen this a good number of times.


The capacitor failing didn't sound right to me as soon as I read it- if caps start to make noise, its usually pretty profound- the sort of thing that has you diving for the power switch- a bad cap can sound like arcing or something burning (which can well be the case).
johnss
569 posts
 
would doubt its caused by static, would vote for one or more cold solder joints somewhere in the signal path.
patrickdowns's avatar
patrickdowns
509 posts
 
I have an Odyssey Khartago++ (upgraded version) and realized after some time with it that I had a low level buzz/hum coming from both speakers, a grounding issue I was told. I didn't realize it was abnormal I guess. My previous amp, a McCormack DNA-1 Deluxe, was dead quiet at idle unless I cranked the volume way up, and then could hear a slight hiss, but no hum/buzz.

I spent a lot of time via email, in a group chat with Klaus and Peter Madnick, who designed my Audio Alchemy DDP-1 (great guy!), troubleshooting it and trying every possible combination of things off/on and plugged/unplugged. Peter admitted that grounding hums can be VERY hard to locate and resolve. The final consensus it is was the amp, so I sent it back. Klaus said he'd found the problem, and offered to upgrade the amp to Kismet level level (his best) at a discount. How could I refuse? It got the best transformer he uses, and other goodies.

When I got the amp back, the buzz/hum is reduced by at least 50% but it's still there. GRRRR. In denial and frustrated, I told myself it was all fixed but it's not. After a month I let Klaus know that it is better but not gone, and NEVER got a reply. More frustration. The amp does sound excellent when playing, and during quiet passages of a track I don't hear the hum/buzz... only at idle.

I haven't taken the time to rip everything apart and put it back one by one, trying different combinations. I'm not good at that. I even thought of buying (w/ 30 day return) an amp or borrowing one to see if I get a buzz/hum with another amp, but haven't yet. In the meantime, I've just let time pass to ease my irritation.

I've checked out the gadgets that PS Audio and others make to address ground hum, but it seems they aren't for amps.

Any suggestions for locating and fixing ground hum would be appreciated. Thanks.
gs5556
1,233 posts
 
It’s not static. Most likely one of the following:

Loose solder joint anywhere, not necessarily just in the signal path. A transistor or diode from the power supply rail to the input or driver stage being cut off will intermittently cut power and also cause "static" noise.

Broken component leads, especially voltage regulators and transistors that have heat sinks attached without the sinks or the device being independently supported off the pcb. This is a common cause of split leads at the pcb and is similar in effect to a bad solder joint.

Damaged transistor insulators. If transistors are removed and the mica insulators are reused, there is a chance of them cracking as the transistors are removed or screwed back in.

I always start by reflowing all solder joints because sometimes it’s difficult to spot a bad joint. 9/10 it fixes the problem.
jetter
3,033 posts
 
Sorry baccus, not sure what’s happening with your amp, but agree with those who think its not static.

patrickdowns, my hum (through the speakers) was being caused because my cable box is running into my preamp. In the end installing one of these into my cable box and the cable company coax into the other end fixed the hum. https://www.parts-express.com/jensen-iso-max-vrd-1ff-75-ohm-inline-digital-catv-isolator-hum-eliminator--246-0121?gclid=EAIaIQobChMIwb-k1dOg7AIVhIjICh1SBgGwEAQYAiABEgLD3vD_BwE

To ensure you just have a ground hum, and there is not something really wrong with your amp, plug the three prong plug into a cheater plug and see if the hum goes away. It did with my amp. Please after doing this check remove the cheater plug as it can be dangerous to use the amp with it installed.
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