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DC Offset Blocker/Killer - where to buy in the USA

   I have McIntosh MC8207, the first unit I bought from an authorized dealer came with a loud buzzing coming from the left transformer, and was replaced with a new unit which came with even a louder buzzing. The buzzing can be heard from 8 feet away. Then I was told to have install new 20 amp outlet that has its own isolated grounding.
   That was done professionally by an electrician who installed two isolated 20 amp outlets, two 20 amp circuit breakers, two copper polls for grounding for each outlet, each outlet has its own neutral and power line. After all this done the buzzing sound was still there.
   I was then told to buy a power conditioner which I did (Audio Quest Niagara) which was like $4000 and that did not help. Called back McIntosh and was told that I might have DC offset in my AC line and was told by McIntosh that I would need a DC Offset Blocker/Killer to which when I asked them where to buy one they told me to go on the internet and search to find one, to which I cannot find one.
  This bothers me a little bit, if you as a company think that I have dc in my ac and i need a dc blocker wouldn't you need to sell one as well. I brought this amp to my friends house and it was the same no improvement, so my guess is that he has dc in the ac line as well.
   So If anyone of you knows where to buy a DC Offset Blocker/killer please let me know, but even if this helps kill the buzzing wouldn't you guys think that this expensive somewhat hifi amp/brand should be silent from the factory. I mean this is two units in a row all purchased brand new.

My house is 5 years old, everything is brand new, the whole neighborhood is about 8-9 years old, my electrician says that I have perfect power coming to the house and everything looks fine.

Thank You

tomiiv30
jea48
2,944 posts
 
@ tomiiv30 OP


Chicago? I didn’t think the city of Chicago AHJ allowed NM sheathed cable, (Romex is a manufacturer’s Trade Name for NM), in residential occupancies. My understanding all branch circuit wiring has to be installed in EMT conduit. Did the electrician install Romex? Is your house wired with Romex? Do you actually live within the city limits of Chicago? 
Jim
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cleeds
2,065 posts
 
jea48
Chicago? I didn’t think the city of Chicago AHJ allowed NM sheathed cable ...
If this guy lives in Chicago, then the work he described would require an electrical construction permit from the city. It would also require that an electrical inspector approve the work before the circuit could be energized. While the permit may cost a few $$$, it would be cheap insurance against the sort of hazardous connections described here.
tomiiv30 OP
63 posts
 
I am outside of Chicago limits about 20 miles west. I just turned off the breaker for that outlet and would not use it until I find somebody that really knows what he does and to double check if everything is correct or not. 



 
cleeds
2,065 posts
 
tomiiv30
... I just turned off the breaker for that outlet and would not use it until I find somebody that really knows what he does and to double check if everything ...
Why don't you get an electrical construction permit? That would probably resolve all of your concerns.
tomiiv30 OP
63 posts
 
Trying to fix the problem for this amplifier's buzz it made a mess of my house electrical. I shouldn't have done anything but just enjoy my new equipment, now we went totally different direction about fixing something that was not broken in the first place.
When I hire someone to do work I expect them to do all the necessary things, if they needed a permit they should've got one, and like I said everything was working just fine before I started adding outlets, even now everything works just fine and maybe everything is correct but I just don't know that what I am saying is correct, maybe I am wording myself wrong.
This problem cost me so much time and money and nerves that is giving me nightmares at night.
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