2. amps-preamps
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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
63 posts
 
@cleeds 

Why do you want to know so bad who the dealer is, I don't get it. What can the dealer do more, I took the amp to them they plugged it in and it was dead quite, what else do you expect to dealer to do. They don't have to do anything else. Now if they cared more about their customers or me as an example they should have went the extra mile to try to help with this situation but they decided that they should not do anything\ but that doesn't mean they did something wrong to me.
On the other hand the manufacturer should've jumped in and try to help me and the dealer as to why is this happening, what can be done, they should've trained the dealer more on how to deal with this kind of situations etc.
Another thing is this amp works there is nothing wrong as far as the output or whatever else, the problem is with the transformer's buzz and this is something that only the manufacturer can fix not the dealer.
I do not want to cause the dealer any harm because I feel that they have not done anything wrong to where I need to bash their name. Even though I was not happy of how they dealt with me I feel that is not enough to put their name in the open forum.
tomiiv30 OP
63 posts
 
@cleeds

Let me get this straight with you, if this amp worked at the dealer place in their tech department and it was dead quite, what case do I have against them or the manufacturer at that point?
So even if I shipped it to MC for warranty repair the same thing would happen at their place to and would say repair is not needed because amp is working properly and there is no buzz.
I demanded that the dealer send somebody to my house or have the dealer contact MC to send somebody out to at least hear this amp’s buzz at my house because in their eyes it looked like I was bullS with them. I still have the amp and it still has that loud buzz and if any of them want to come out to my place to check it out they are more than welcome. So far nobody has reached out to me to make a visit to hear their product not working as it should.
Let's see if they are going to do that
cleeds
2,065 posts
 
tomiiv30
Why do you want to know so bad who the dealer is, I don't get it ...
You've stated that, "no one from the dealer or the manufacturer cared to find a solution to my problem," so it's reasonable to ask who the dealer is.
the manufacturer should've jumped in and try to help me
It still isn't clear why you don't simply return the amp to McIntosh for evaluation and (hopefully) repair.
tomiiv30 OP
63 posts
 
@cleeds 

It still isn't clear why you don't simply return the amp to McIntosh for evaluation and (hopefully) repair

Because it would cost me more money to do so, I have to pay for shipping both ways which is not cheap, and I am not planning to spend a cent more because I am pretty sure nothing would get done.


jetter
1,035 posts
 
I think cleeds is right about sending the amp to McIntosh to be checked out so you at least have a record with them of attempting to fix the problem.  I am assuming you only would be paying for shipping as the unit is under warranty?  Take this with a grain of salt as I haven't had a similar problem, but I would have expected a good dealer to send it for warranty work whether they could hear the problem or not.  You have the you tube video as proof of the hum.
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