Ain't gonna happen..... It's the nature of the beast. DC voltage interring the primary winding of a toroid transformer will cause mechanical noise.
Rakuennow
However, the consensus seems to be that all quality Toroids and modern electric equipment should be sufficient at removing DC.
That is, if there is DC voltage on the mains.
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The ones proposing DC as a main problem all seem to be selling something..
Nelson Pass nor Eva Manley are trying to sell devices to filter out DC voltage.
For a few bucks you can build a DC blocking filter as Pass and Manley talked about in their posts on DIY
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I'm entertaining, though, one alternative option. I could try to sell my Panamax "line conditioner", and buy a used voltage regulator, which should take care of magnetostriction, and to my underestanding, DC as well. Are there any opinions on this?I suggest you first check the back of the Amp and see what the manufacture voltage rating is. Is it 120V or 115V?
Even if it is 120V 10% under would put the voltage at 108V.
Then there is your meter...... How accurate is your meter?
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Ngjockey
Should also mention that the reason you don't see a lot of the Channel Islands type of thing and why the DaBlok is DIY is because capacitors aren't intended for AC mains and there is a slight chance of the caps going "poof" or "bang". No, we're not talking dynomite here but it's scary enough for manufacturers. Thus, the heavy duty case, expensive components and the cost.
Ngjockey, if it is a concern a fuse could always be placed ahead of the filter circuit.
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