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

miner42
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You spend many $$$$ on the equipment yet you cry about spending $ to send to a service center when you probably have a service center near you that you could deliver to."

I wonder if this OP ever submitted his amplifier for a proper, qualified, thorough bench testing by a factory authorized engineer or technician to establish beyond any doubt for certain whether the amplifier is in some way broken, faulty, or defective or if the source, origination, and cause of the problem is elsewhere. I applaud the OP's courage, bravery, and persistence in pursuing this problem and can only wonder what prevented him from seeking verified, documented, testable proof and validation of the issue here.
@clearthink

   Just to update you on your question if I ever did anything else with this amp and the answer is NO I did not because it is not worth my time, it is what it is I am using it as is and am trying to enjoy it while I have it.
   
But it is for sale locally, once I sell it I will be moving to something else for my Home Theater and to a company with a better customer service and followers. I have been jumped and called names from so many Mac followers about this issue ain't even funny.

   As for the other Mac equipment that I have the MC462 and C52 those are keepers and love them both even though I had some hiccups with the MC462 having lose parts but it was replace with a new unit by the dealer and is all good now.

   Just upgraded my stereo speakers and got myself a new pair of Dynaudio Contour 60 and are in their break in period as I write this post. So far I am very pleased with them and will make a separate post about them.