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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
tomiiv30 OP
65 posts
 
Would you guys be surprised if I told you nothing happen out of this situation. I get to keep this amp the way it is, it’s been over their return policy period and nobody cares to even take a look or find a solution to a problem that not just me but others are having and it is very common within McIntosh amps.
I can tell you that nobody gives a flying f$%k about the consumer anymore, they just want your money and that’s that. Once you pay you are alone and that’s how I feel.
The salesman could do just so much, he is there just like a middleman without having any authority over anything except to sell and make management happy. Even he admit it that this place sucks balls so what would you expect from place like that.
Learnt from my own mistakes but I ain’t getting screwed again after this kind of treatment that I got from Manufacturer and Dealer.

$30K in the hole and not one phone call to me. I was better treated when I bought a $200 item and was make sure I was happy with my purchase.
tomiiv30 OP
65 posts
 
Here is everything that went wrong from day one:

Purchased demo unit MC452 and came to me broken, right side was running way hotter than left side, had to return it and got refund back.

Purchased brand new MC8207, MC462: First MC8207 had a buzz and was replaced with a second that had even louder buzz to where you can hear it the other room.
MC462 had loose parts from the get go and it was replace by a second unit that had all parts intact but very bad quality check, the chassis itself has very bed edge to where you can cut yourself, but since I can't take it anymore I just decided to keep the second unit and live with it.

As you can see lately their quality check sucks big time. It's not just one thing but there is plenty other things happening.

The only thing that came perfect was the Marantz AV8805 that I purchased brand new as well when I bought the MC8207


jea48
4,560 posts
 
@ tomiiv30 OP

How about an update on your electrical. Did the electrician come out and check for possible electrical problems in your home?

Possibly loose and or corroded wire connections in the electrical service panel?

Have you spoken to any one yet from your utility power company?

Jim


tomiiv30 OP
65 posts
 
Yeah he came to the house checked everything again and he said not to call him any more, he thinks that I am bulls^&#g with him, and that's why I did not write anything about it. I feel like I have been let down, like I said this were the worse $30K spent in my life. 

Talking to the electrical company is like talking to my 5 year old. I just don't have the nerves and time anymore and would just live with it, I got so tired of this whole situation that I gave up.
jea48
4,560 posts
 
Yeah he came to the house checked everything again and he said not to call him any more, he thinks that I am bulls^&#g with him, and that's why I did not write anything about it.
What did you find out about how the electrician wired the two ground rods to the two new wall outlets for the two new dedicated branch circuits you had him install?
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