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

Showing 4 responses by 4krow

I will be most interested in how this all plays out. When there is a problem like this, and it ONLY EXISTS with the unit being suspected, AND it has the same problem in someone else's home as well,, Good Lord, it is more than reasonable to get a Full refund. 
Well,  If you find yourself in the same position as the OP, then demand a full refund, and find unit that does not have this problem. Been there, done that.
And round and round we go. It's this, it's that, believe me. You made a simple case for me anyway. You took the unit to 3 different houses miles apart from each other with the same humming result. What more has to said? Defective unit, no?
Ok, so from reading all this and assuming that everyone did the best that they could, I would be wary of buying a Mac unit, period. All the other equipment he owns has no trouble, but this unit, and even another replacement unit does.