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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
4,517 posts
 
@ tomiiv30 OP

I think the reason the DC blocker you got may not be working correctly is because it doesn’t have a large enough ampere rating. Does it give an, ampere rating on it anywhere? I believe you are going to need one that is made for a big power amp.

There is an Agon member that used to build DC blockers. I will see if I can find his user name.
jea48
4,517 posts
 
@ tomiiv30 OP

The Agon member’s username is gbart. Send him a PM. I don’t know if he still makes them though. Make sure you give him the specs for the amp.

https://www.audiogon.com/users/gbart

.



audioman58's avatar
audioman58
4,214 posts
 
That is total BS,especially after bringing to another persons house
that is a defect in the unit period.
i sold McIntosh and they should take the unit back and fix the dam
thing. Take it over one more persons house , if still an issue you know they are full of crap. Their integrity is not what it used to be 
I have found a lot of parts in there that a $6k amp should not have 
$3.00 Wilma caps instead of aa much higher caliber  type  as well as resistors ,even dipping more into Chinese parts . There transformers used to be made in California , that changed in 2010
where are they Built now ?  . Is it still under warranty ? If so send it back, your dealer should be backing you  ,try a different power cord just to make sure a ground didnot seperate,  i Never had one do as you mentioned. If not in warranty bring to a  technician  to get a evaluation  it sounds totally out of line  . One more thing 
did you change anything ?  Put another amp in Your system  
and if no issue then it is  your amp.
Ag insider logo xs@2x
cleeds
6,017 posts
 
audioman58
That is total BS ... that is a defect in the unit period ... they should take the unit back and fix the dam
thing ... Their integrity is not what it used to be ...
I agree that there’s nonsense going on here - the facts just do not add up. The OP has deleted his original post here about the problems and disappeared from this forum and the other forum where he raised these issues. He won’t identify his dealer - even though the dealer doesn’t seem to have been very helpful in resolving the problem - and he has refused to return the unit to McIntosh for evaluation. So it’s really impossible to know what’s going on.
There transformers used to be made in California ...
They’ve always been hand-wound in Binghamton, afaik.
tomiiv30 OP
65 posts
 
@cleeds 

What are you talking about, what have I deleted from this thread, everything that I have posted is still here and I have not disappeared I am still here but have nothing else to add to it, I am keeping the amp as is and I will never ever buy another McIntosh product in my life, simple as that.
When the dealer and the manufacturer do not give a flying F about their customer, what else can a customer do except keep the amp because like I said before this amp when I took it to the dealer and once they plugged it in their outlet it was dead quite, why is it buzzing at my house and at my friend's I have no idea, all I was told is that I have or we have bad electricity that's all, I am no planning to repeat myself again everything is noted in this thread if you want to find out more please read the whole thing.
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