clinic-audio
all on YAMAHA untill 1990
TOM
The noise that you take time to record is a singing toroidal power transformer because of DC on your local AC line
DC Offset Blocker/Killer - where to buy in the USA - for MC8207
- Thread starter TomIV
- Start date
TOM
The noise that you take time to record is a singing toroidal power transformer because of DC on your local AC line
First of all, are you smoking crack or what?
1. Which part of I turned all the switches off don't you understand (from the main panel that is in my basement) and had wife on phone turning on or off one by one. I think you are the one jerking me around that's why I got upset with you in the earlier posts.
2. This is what I have been told to do from the dealer to the manufacturer, I was asked if I had dedicated 20 amp outlets since at the very begging I did not have but installed not 1 but 4 total and 1 of the 4 has its own isolated ground that comes from the outlet itself directly to a copper poll that is installed in the ground and this grounding wire has nothing to do with anything else in the house. The other 3 do have their grounding but not as isolated as the other one. (And you know why I did this because again, I was told by Mac, that I have ground loop - this was the first thing I was told.
3. I was told by the dealer this would help
4. I did not take this amp to my neighboor first of all, I took it to 2 of my friends houses who live 20 miles apart from me. If you red my earlier posts you would've known by now.
5. It was the very first amp that I returned to the dealer who at the moment when I was at the store told me they were busy and could not test, but few day later they emailed me and said they hear nothing, to which I bet that they are full of crap or they have used some kind of a DC blocker that is way stronger than the CMX-2
- I will be taking this second amp to them tomorrow and will have them test it in front of me, but first I would ask them to send a tech or an expert fromm their own to come to my house to note everything that has been happening and all the things I have done.
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But he clearly says that he does not believe that I have turned all the breakers off except the one for the amp. What else does he expect me to do go knock on my neighbors door and have them turned their power off.
If you are asking me, I am using only one 7 channel amp hooked up the the AV8805 for my home theater which is the 8207.
My MC462 and C52 is a separate system that has nothing to do with the Home Theater.
What matters is that you need your dealer's representative to document the issue and bring you a check until it can be made right.
Patrice as a respected tech in Paris has seen this problem m much more often than any of us because he services other brands that have used toriodal transformers longer than Mac has.
http://sound.whsites.net/articles/xfmr-dc.htm
Rod Elliot posts a interesting technical analysis of this up and coming problem. Posted ten years ago it shows how far so many of us behind.
Patrice as a respected tech in Paris has seen this problem m much more often than any of us because he services other brands that have used toriodal transformers longer than Mac has.
http://sound.whsites.net/articles/xfmr-dc.htm
Rod Elliot posts a interesting technical analysis of this up and coming problem. Posted ten years ago it shows how far so many of us behind.
clinic-audio
all on YAMAHA untill 1990
TOM
First of all, are you smoking crack or what ? I work always with a clear mind which is necessary when you make my job and I can add that I don't smoke (anything)
1. Which part of I turned all the switches off don't you understand (from the main panel that is in my basement) and had wife on phone turning on or off one by one. Because you don't know that this is not disconnecting everything from your electrical circuit and that's what I think when you said you did make the test . Disconnecting this way is fast but not invasive you are not sure that something stay may be connected but it is not important
2. This is what I have been told to do from the dealer to the manufacturer, I was asked if I had dedicated 20 amp outlets since at the very begging I did not have but installed not 1 but 4 total and 1 of the 4 has its own isolated ground that comes from the outlet itself directly to a copper poll that is installed in the ground and this grounding wire has nothing to do with anything else in the house. The other 3 do have their grounding but not as isolated as the other one. (And you know why I did this because again, I was told by Mac, that I have ground loop - this was the first thing I was told. Making this is not a bad idea but can not resolve this kind of trouble
3. I was told by the dealer this would help , maybe in some conditions, yes
4. I did not take this amp to my neighboor first of all, I took it to 2 of my friends houses who live 20 miles apart from me. If you red my earlier posts you would've known by now . I have read your messages
5. It was the very first amp that I returned to the dealer who at the moment when I was at the store told me they were busy and could not test, but few day later they emailed me and said they hear nothing, to which I bet that they are full of crap or they have used some kind of a DC blocker that is way stronger than the CMX-2 don't be suspicious like that , what will be their interest to lie if they replace the first one by another one and use a DC blocker instead to sell you the same and get the peace , don't you think ?
- I will be taking this second amp to them tomorrow and will have them test it in front of me, but first I would ask them to send a tech or an expert fromm their own to come to my house to note everything that has been happening and all the things I have done. An expert to your home is possible but after one simple thing : If they made a listening test in front of view at the dealer shop ,what will you think if you don't hear yourself any noise ?
As Chris precise , I met this trouble more than once and this si not true only with MCINTOSH MC8207 it will be the same ( or worse ) with any very big toroidal power transformer
I honestly don't think that you have the necessary tools to check if localy you have problem in your house
You can try to ask to some tech to build what I show in the schematic I have posted some days ago . There is a great interest : it is costing peanuts for you and maybe clear for ever your trouble with your amplifier .
Personnally I would prefer to try and it is not really heavy comparing with your MC8207
Chris said also :
Rod Elliot posts a interesting technical analysis of this up and coming problem. Posted ten years ago it shows how far so many of us behind. YES , we can see it today and as you said many manufacturer should think about it .
I did not wrote in RED because I am not mad against you
First of all, are you smoking crack or what ? I work always with a clear mind which is necessary when you make my job and I can add that I don't smoke (anything)
1. Which part of I turned all the switches off don't you understand (from the main panel that is in my basement) and had wife on phone turning on or off one by one. Because you don't know that this is not disconnecting everything from your electrical circuit and that's what I think when you said you did make the test . Disconnecting this way is fast but not invasive you are not sure that something stay may be connected but it is not important
2. This is what I have been told to do from the dealer to the manufacturer, I was asked if I had dedicated 20 amp outlets since at the very begging I did not have but installed not 1 but 4 total and 1 of the 4 has its own isolated ground that comes from the outlet itself directly to a copper poll that is installed in the ground and this grounding wire has nothing to do with anything else in the house. The other 3 do have their grounding but not as isolated as the other one. (And you know why I did this because again, I was told by Mac, that I have ground loop - this was the first thing I was told. Making this is not a bad idea but can not resolve this kind of trouble
3. I was told by the dealer this would help , maybe in some conditions, yes
4. I did not take this amp to my neighboor first of all, I took it to 2 of my friends houses who live 20 miles apart from me. If you red my earlier posts you would've known by now . I have read your messages
5. It was the very first amp that I returned to the dealer who at the moment when I was at the store told me they were busy and could not test, but few day later they emailed me and said they hear nothing, to which I bet that they are full of crap or they have used some kind of a DC blocker that is way stronger than the CMX-2 don't be suspicious like that , what will be their interest to lie if they replace the first one by another one and use a DC blocker instead to sell you the same and get the peace , don't you think ?
- I will be taking this second amp to them tomorrow and will have them test it in front of me, but first I would ask them to send a tech or an expert fromm their own to come to my house to note everything that has been happening and all the things I have done. An expert to your home is possible but after one simple thing : If they made a listening test in front of view at the dealer shop ,what will you think if you don't hear yourself any noise ?
As Chris precise , I met this trouble more than once and this si not true only with MCINTOSH MC8207 it will be the same ( or worse ) with any very big toroidal power transformer
I honestly don't think that you have the necessary tools to check if localy you have problem in your house
You can try to ask to some tech to build what I show in the schematic I have posted some days ago . There is a great interest : it is costing peanuts for you and maybe clear for ever your trouble with your amplifier .
Personnally I would prefer to try and it is not really heavy comparing with your MC8207
Chris said also :
Rod Elliot posts a interesting technical analysis of this up and coming problem. Posted ten years ago it shows how far so many of us behind. YES , we can see it today and as you said many manufacturer should think about it .
I did not wrote in RED because I am not mad against you
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@clinic-audio
Let say I take this amp to the dealer and there is no buzz. But the same amp buzzes in my house and my friends houses.
Whos fault is it? Is it the consumer's fault who I bet 90% would have no idea what to do and what to look for or is the manufacturer's job to tell us the consumer that their amps could and would buzz if there are some imperfactions with our power and or dc offset problems, it is not happening only to me but it has happened to many of us.
Shouldn't the manufacturer and the dealer writte a disclaimer on the invoice that if this amp buzzes to be able to return it no questions ask.
If I knew about this problem before I bought the 8207 I wouldn't buy and that's that simple. But not one dealer that I have visited ever told the whole truth about this amp and the 207 as a matter of fact.
Let say I take this amp to the dealer and there is no buzz. But the same amp buzzes in my house and my friends houses.
Whos fault is it? Is it the consumer's fault who I bet 90% would have no idea what to do and what to look for or is the manufacturer's job to tell us the consumer that their amps could and would buzz if there are some imperfactions with our power and or dc offset problems, it is not happening only to me but it has happened to many of us.
Shouldn't the manufacturer and the dealer writte a disclaimer on the invoice that if this amp buzzes to be able to return it no questions ask.
If I knew about this problem before I bought the 8207 I wouldn't buy and that's that simple. But not one dealer that I have visited ever told the whole truth about this amp and the 207 as a matter of fact.
clinic-audio
all on YAMAHA untill 1990
Tom
Let say I take this amp to the dealer and there is no buzz. But the same amp buzzes in my house and my friends houses. if it is the case this fact will proove you that the amplifier is not bad
Whos fault is it ? not yours of course !
90% would have no idea what to do , yes , I am OK with that but in my point of view , dealers know many differents circumstances of noise generated here and not there ..
I think that dealers are there first , to give good advise , and should be very informed by manufacturers about specific circumstances during possibilities of noises generated by their item
If I knew about this problem before I bought the 8207 I wouldn't buy and that's that simple. no , I think that if your listen it before to buy it at dealer shop , you don't hear any noise and buy it . If the first one stay at the dealer shop today , try to listen this one , this will avoid you to cary heavy unit for nothing .
it is not happening only to me but it has happened to many of us. I hope that "many of us " are reading AK right now , and are aware !
Let say I take this amp to the dealer and there is no buzz. But the same amp buzzes in my house and my friends houses. if it is the case this fact will proove you that the amplifier is not bad
Whos fault is it ? not yours of course !
90% would have no idea what to do , yes , I am OK with that but in my point of view , dealers know many differents circumstances of noise generated here and not there ..
I think that dealers are there first , to give good advise , and should be very informed by manufacturers about specific circumstances during possibilities of noises generated by their item
If I knew about this problem before I bought the 8207 I wouldn't buy and that's that simple. no , I think that if your listen it before to buy it at dealer shop , you don't hear any noise and buy it . If the first one stay at the dealer shop today , try to listen this one , this will avoid you to cary heavy unit for nothing .
it is not happening only to me but it has happened to many of us. I hope that "many of us " are reading AK right now , and are aware !
@clinic-audio
Let say I take this amp to the dealer and there is no buzz. But the same amp buzzes in my house and my friends houses. if it is the case this fact will prove you that the amplifier is not bad - What if the dealer is using very expensive device that will silence the transformer, how would I know what they are using - If there is such a thing.
Whos fault is it ? not yours of course ! I hope it's not mine
90% would have no idea what to do , yes , I am OK with that but in my point of view , dealers know many different circumstances of noise generated here and not there ..
I think that dealers are there first , to give good advise , and should be very informed by manufacturers about specific circumstances during possibilities of noises generated by their item - The dealer I bought it from had no idea about DC offset all the crap that is associated with, if they knew probably they would've told me what to look for in the first place and not order a new amp to replace the first one. Simply put my dealer was not educated by McIntosh of how to handle this kind of situations.
When I told my dealer that my very first amp 8207 had a hum they were the ones that told me they gonna replace it with another brand new amp, if they knew about this problem don't you think they would've sent somebody to my house to inspect everything before they ordered a new one. I did not make them order me a new amp it was their suggestion.
If I knew about this problem before I bought the 8207 I wouldn't buy and that's that simple. no , I think that if your listen it before to buy it at dealer shop , you don't hear any noise and buy it . If the first one stay at the dealer shop today , try to listen this one , this will avoid you to carry heavy unit for nothing . - Of course I would've listen to it if I knew about this problem before, but this problem is very new to me and it was my wife who noticed the buzz / hum first before me, I was so happy about the equipment I bought that I did not notice it right away. And I bet you that many other McIntosh MC8207 or MC207 think that this hum / buzz problem is normal and would never complain because they don't know any better.
it is not happening only to me but it has happened to many of us. I hope that "many of us " are reading AK right now , and are aware ! I hope that they are reading this kind of posts before they make their purchase at least they can get some free education on my dime.
Let say I take this amp to the dealer and there is no buzz. But the same amp buzzes in my house and my friends houses. if it is the case this fact will prove you that the amplifier is not bad - What if the dealer is using very expensive device that will silence the transformer, how would I know what they are using - If there is such a thing.
Whos fault is it ? not yours of course ! I hope it's not mine
90% would have no idea what to do , yes , I am OK with that but in my point of view , dealers know many different circumstances of noise generated here and not there ..
I think that dealers are there first , to give good advise , and should be very informed by manufacturers about specific circumstances during possibilities of noises generated by their item - The dealer I bought it from had no idea about DC offset all the crap that is associated with, if they knew probably they would've told me what to look for in the first place and not order a new amp to replace the first one. Simply put my dealer was not educated by McIntosh of how to handle this kind of situations.
When I told my dealer that my very first amp 8207 had a hum they were the ones that told me they gonna replace it with another brand new amp, if they knew about this problem don't you think they would've sent somebody to my house to inspect everything before they ordered a new one. I did not make them order me a new amp it was their suggestion.
If I knew about this problem before I bought the 8207 I wouldn't buy and that's that simple. no , I think that if your listen it before to buy it at dealer shop , you don't hear any noise and buy it . If the first one stay at the dealer shop today , try to listen this one , this will avoid you to carry heavy unit for nothing . - Of course I would've listen to it if I knew about this problem before, but this problem is very new to me and it was my wife who noticed the buzz / hum first before me, I was so happy about the equipment I bought that I did not notice it right away. And I bet you that many other McIntosh MC8207 or MC207 think that this hum / buzz problem is normal and would never complain because they don't know any better.
it is not happening only to me but it has happened to many of us. I hope that "many of us " are reading AK right now , and are aware ! I hope that they are reading this kind of posts before they make their purchase at least they can get some free education on my dime.
I don't know yet, I have to find out what's gonna happen with this unit still and if I decide I need to return it and get a refund than I would start looking at other options for my home theater amp. If they can get me a unit that would not buzz without any dc blockers and whatnot than I would stick to the mc8207 and McIntosh for my HT and if not than It would be a search of a new brand and demoing and making smarter choices from now on, it has been a learning experience for me for sure with this purchase and it was my very first expensive some what hifi equipment buy.
Update:
Went to the dealer today with the MC8207 and right away I was taken upstairs to their tech department where they plugged this amp and the result was a dead quite none buzzing transformer and I mean dead quite not even a small buzz. Now I don't know if their outlets have been treated since this is the tech department and not any other place in the store, it was the only place that we tested it. I was very surprised and happy at the same time knowing that this amp can be quite so I guess it leads me back to my house or the outside power.
I am in a search of somebody that really knows how to measure DC offset in the AC lines, I did what McIntosh told me to do and it returned 0.9mV which is nothing to make the transformer buzz but it could've been a wrong measurement.
As for the LED Lights that were not illuminating equal Left Side to Center to Right, there was a slight shift of an inside part that the tech had to open the front and fix it to make it all Illuminate the same, bear in mind this is a brand new amp and it needed to be open to be fixed.
I have already spoken to my electrician who is coming back to the house to do an extensive checking and we would be unplugging everything from the outlets and I mean everything, and will be turning off all the breakers off except the one for the amp and see if we can finally find the problem and if that doesn't help than it would be the right time to call the electric company to do their part, because otherwise it would be very hard to convince them to come out just because I have a buzz.
I am a person that do not give up and would like to find a solution to fix this problem no matter what it takes as long as it is fixable.
And if anyone from here ever had to deal with their electric company would you be kind to share the steps taken to convince them to come out.
Went to the dealer today with the MC8207 and right away I was taken upstairs to their tech department where they plugged this amp and the result was a dead quite none buzzing transformer and I mean dead quite not even a small buzz. Now I don't know if their outlets have been treated since this is the tech department and not any other place in the store, it was the only place that we tested it. I was very surprised and happy at the same time knowing that this amp can be quite so I guess it leads me back to my house or the outside power.
I am in a search of somebody that really knows how to measure DC offset in the AC lines, I did what McIntosh told me to do and it returned 0.9mV which is nothing to make the transformer buzz but it could've been a wrong measurement.
As for the LED Lights that were not illuminating equal Left Side to Center to Right, there was a slight shift of an inside part that the tech had to open the front and fix it to make it all Illuminate the same, bear in mind this is a brand new amp and it needed to be open to be fixed.
I have already spoken to my electrician who is coming back to the house to do an extensive checking and we would be unplugging everything from the outlets and I mean everything, and will be turning off all the breakers off except the one for the amp and see if we can finally find the problem and if that doesn't help than it would be the right time to call the electric company to do their part, because otherwise it would be very hard to convince them to come out just because I have a buzz.
I am a person that do not give up and would like to find a solution to fix this problem no matter what it takes as long as it is fixable.
And if anyone from here ever had to deal with their electric company would you be kind to share the steps taken to convince them to come out.
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Our local electrical company had a person who would install the companies monitoring equipment to a service to record the draw and supplied voltage to the service.
He happened to be a customer of mine. Twice I let him know of a client with power issues and both times he installed the monitoring equipment and both times wrote up job orders to replace the power pole transformers to those houses which were defective.
All power companies have to have these techs and I am sure your electrical contractor will know who to contact within the power company.
Press your local electrician to reach out for you.
He happened to be a customer of mine. Twice I let him know of a client with power issues and both times he installed the monitoring equipment and both times wrote up job orders to replace the power pole transformers to those houses which were defective.
All power companies have to have these techs and I am sure your electrical contractor will know who to contact within the power company.
Press your local electrician to reach out for you.
Wow! So what McIntosh told you as well as those knowledgeable members of this board was true.
Humbling...
Larry
Humbling...
Larry
I still haven't found dc on my ac line, i am in a search of a person that can take a measurement different way than the way i did it and was told by mc. And I still believe that MC should invent something to install i their units that have this kind of transformers.
I have done everything I was told to do. And how do I know the dealer is not using something to silence this knowing issue. The room I was taken to it was like being in NASA.
How is it my fault, I am just a consumer who spent $25K on McIntosh brand to have this so called singing transformers. There is plenty of people who have this problem and not many even know they have it and this has to be fixed somehow and not have us the consumer spend extra money and time.
I have done everything I was told to do. And how do I know the dealer is not using something to silence this knowing issue. The room I was taken to it was like being in NASA.
How is it my fault, I am just a consumer who spent $25K on McIntosh brand to have this so called singing transformers. There is plenty of people who have this problem and not many even know they have it and this has to be fixed somehow and not have us the consumer spend extra money and time.
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And I can tell you that quality control check is suffering big time.
MC8207 - first one and second one buzz, second one messed up led lights and bent metal plate.
MC462 - first one had lose metal plates on the back and it was replaced with a second that has all the parts intact but very sharp edges where one can get a cut, but this time would not complain any more because I don't have nerves any more and am exhausted from all the heeavy lifting and will keep the second one as is but I know I will have problems selling it down the road.
And if you didn't know this is a premium brand that costs some serious money to own and one would expect perfection from it, and can't blame the dealer for this kind of situations, they tried to do as much as they could and wanted to make me happy at the end thanking my sales man because if it wasn't for him this wouldn't have happened.
MC8207 - first one and second one buzz, second one messed up led lights and bent metal plate.
MC462 - first one had lose metal plates on the back and it was replaced with a second that has all the parts intact but very sharp edges where one can get a cut, but this time would not complain any more because I don't have nerves any more and am exhausted from all the heeavy lifting and will keep the second one as is but I know I will have problems selling it down the road.
And if you didn't know this is a premium brand that costs some serious money to own and one would expect perfection from it, and can't blame the dealer for this kind of situations, they tried to do as much as they could and wanted to make me happy at the end thanking my sales man because if it wasn't for him this wouldn't have happened.
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I read or heard somewhere Mac was bought out by foreign company. Maybe it's the beginning of the new company cutting corners to make there money back.
Oh and they are raising prices too.
bob06
Addicted Member
There you go. Another company will bite the dust.
