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The Perseus I bought about nine years ago, in spite of otherwise sounding very nice, has always had a noise problem. Essentially a high-pitched hum/low-pitched buzz- 60 Hz harmonics, I assumed, at a constant level, not VC-dependent. Had just lived with it lo these many years but was getting frustrated. Wasn't convinced that the factory was going to be helpful, and thus decided to take a whack at it myself. So I removed the top, removed the toroidal transformer retaining nut, and propped the transformer up on a plastic foam block so that it was raised up about three inches from its usual position at the bottom of the case. Voila'! Noise reduced about 80%.
However, I didn't want to use it like that, as I could no longer put the top cover back on. So I replaced the transformer back to its usual spot but tried rotating it about 90 degrees, the wires fortunately being long enough. Now had noise reduction of about 70%, and I can live with that. Would love to hear any insights on this from anyone in the know.
Mark in NC
"The thought that life could be better is woven indelibly into our hearts and our brains" -Paul Simon
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I had a hum from my Rogue Sphinx and fixed it by placing an "Ebtech Hum X" between it and my PLC. It was about $60 from Amazon years ago; I don't know what they cost now.
I would think you can raise it a little without hitting the top?
Tried that, but it didn't work. Only way to get significantly reduced noise was to raise it several inches, or rotate it in its usual spot, leads fortunately permitting. As it stands, it's not dead quiet but very tolerable, much better than before. Also, radiating from large Maggies, the noise that's left is somewhat "diffused" so is less noticeable. Thanks for the suggestion, though. It was just really gratifying solving this problem on my own.
Mark in NC
"The thought that life could be better is woven indelibly into our hearts and our brains" -Paul Simon
Even a strip as tall as depth of chassis, wrapped around transformer. and grounded.
The little hole for the wires will not be a problem.
If you prefer not isloating the analog circuitry from the xfrmr by separation distance, perhaps some magnetic shielding could offer you even more immunity to the noise. Something like some mumetal might help divert that noise energy to someplace less consequential to the audio.
I had given a bit of thought to that, as there's still some room left, I believe, to reduce the noise level further. Not having had any experience with mu-metal, are there any tips/techniques for using it effectively?
Mark in NC
"The thought that life could be better is woven indelibly into our hearts and our brains" -Paul Simon
I've never owned any. As I understand it it will be most effective for certain bands of B field.
If that isn't working try an E field shield such as some copper.
Rules of thumb for shields: 1. the more you can completely enclose the noise source by continuous shielding the better. 2. Thicker is better 3. with the e field shield, try floating, earthing, etc.
nt.
"The thought that life could be better is woven indelibly into our hearts and our brains" -Paul Simon
Transformers are very interesting components within the structure of a tube amp.
beyond the assembly and finish of the transformer, the orientation IS important. Glad that you found a solution- it makes sense that it worked out that way.
Happy Listening
By all accounts Rogue has about the best customer service there is and in all those years you never reached out to them?
___
"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."
First, based on other people's experiences with the same problem as read on various audio forums over past years. Second, when I called them to report my initial findings to ask them how to get the same results with the transformer back in original position, they couldn't really offer any help. It was just through happenstance that I tried rotating it. The problem had been lower priority for me after having fixed my C-J PF-R not too long ago, thereby allowing me to use it, but that repair (an intermittent problem that the C-J service dept. was unable to diagnose) motivated me to take a whack at the Rogue problem.
Mark in NC
"The thought that life could be better is woven indelibly into our hearts and our brains" -Paul Simon
From my experience, using Conrad Johnson's service department, was a total disaster. They replaced one resistor on a 17LS pre-amp, charge $420.00.
5 Week turnaround time.
Never again will I purchase a CJ product.
nt.
"The thought that life could be better is woven indelibly into our hearts and our brains" -Paul Simon
It was a specially tuned audiophile grade resistor that was highly praised in various magazine reviews. ;-)
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