In Reply to: RE: Isolation Transformer For Digital Sources? posted by lowrider75 on June 24, 2016 at 23:26:42:
Okay, this is as I had suspected. A high pitched noise is likely not due to a mains ground loop. You may be experiencing either RF intrusion, or some gain stage oscillation (oscillation is more my suspicion, since the noise only appears after warm up). So, we appear to have reduced the possibility of the digital source components, the interconnects or the power amp being the problem. I say the power amp too, because the noise stops once you mute the preamp output feeding the amp. Signs appear to be pointing to the preamp.Next, I suggest bypassing (completely removing) your Atma-Sphere preamp from your system chain. If you don't have a second preamp unit laying around in your basement then beg, borrow or steal one from a friend. Any cheap unit will do, the quality doesn't matter for your noise isolation test purposes. If you cannot access another preamp from somewhere, then perhaps your Chord DAC features a built in volume control, enabling it to be directly connected to your power amp.
If the preamp turns out to be the source of the noise, it may have a bad tube or a tube with pins poorly contacting it's socket. If it's not due to something easy to fix yourself, like that, then the preamp will probably need professional servicing. If the problem turns out NOT to be the preamp then, unfortunately, it would be hard to determine where else to point you via remote troubleshooting. So, keep your fingers crossed. :)
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Ken Newton
Edits: 06/25/16 06/25/16 06/25/16 06/25/16 06/25/16 06/25/16
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Follow Ups
- RE: Isolation Transformer For Digital Sources? - knewton 05:48:57 06/25/16 (4)
- RE: Isolation Transformer For Digital Sources? - lowrider75 19:11:31 06/25/16 (3)
- RE: Isolation Transformer For Digital Sources? - motberg 04:49:18 06/28/16 (1)
- RE: Isolation Transformer For Digital Sources? - lowrider75 18:38:20 06/28/16 (0)
- RE: Isolation Transformer For Digital Sources? - knewton 08:30:09 06/26/16 (0)