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.
Question is why would you still want to buy a McIntosh product after hearing the way they have treated the OP? Ron ( McIntosh representative) said maybe 5 complaints a year about torid buzzing power transformers. You want to beat the number of complaints is actually higher than 5?
How much would it have cost for McIntosh to incorporated a DC blocker in the MC8207 amp? I would be willing to bet the design engineer first designed the amp with a DC blocker. No doubt the design engineer new that a large torid power transformer would vibrate/buzz if there was DC offset on a customer’s AC mains. How much you think them pretty covers cost that cover the transformer and DC power supply inside the MC8207? Or them big pretty blue front meters? They sure look pretty though don’t they?
Charlie Randall (top USA dog now) is already starting to make ARC equipment look like McIntosh.
... why would you still want to buy a McIntosh product after hearing the way they have treated the OP?
Because we don’t know how McIntosh treated the OP - it’s just hearsay from an anonymous poster. On the other hand, I have years of first-hand experience with Mac.
Charlie Randall (top USA dog now) is already starting to make ARC equipment look like McIntosh
ARC doesn’t look at all like Mac - ARC has rack width; choice of silver or black finish; no blue meters or logo in a Gothic font ...
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.
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
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.
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?
It is one rod that he installed in the ground that is few feet away from the outside meter/box, the other rod was installed form the electrical company, it was already there, that's why I thought he did 2.
One of the 20 amp outlet is grounded to the inside of the panel.
The other 20 amp outlet is grounded directly from the outlet to the outside rod with a clamp that is attached to the rod itself, I saw that with my own eyes. It is a straight wire that goes from the outlet to the outside and has nothing to do with the inside panel or anything else in the house.
Both these outlets are on it's own there are not shared with any other outlets in the house.
He did measure few different things he would not let me tell him anything he just said everything measures fine. I know I saw him measuring on the panel where he got 240 volts and said one is 120 and the other is 120 something in those lines. He measured the outlets too, I don't know what he was doing but after he was done he said that to him everything looks good and he said good like convincing the electrical company to come out.
That's all I have. And I am not planning to spend any more time nor money to call other electricians or whatnot.
I did not read the whole thread so sorry if this was addressed. doesn't Mac use transformers for coupling? so maybe there is only one power transformer that's why only one is humming. The others could be for coupling.
The other 20 amp outlet is grounded directly from the outlet to the
outside rod with a clamp that is attached to the rod itself, I saw that
with my own eyes. It is a straight wire that goes from the outlet to the
outside and has nothing to do with the inside panel or anything else in
the house.
If you're in the U.S., that's a violation of the NEC and is potentially hazardous. It also creates a potential ground loop, which can only exacerbate your problems.
What is the difference between the ground wire that is connected to the panel itself and the one that goes to the outside, it still goes thru the panel but it is not attached to the panel itself it just goes thru the pipe that goes outside where the meter is and from there it is attached to the rod. I am by no means an electrician and I am trying the understand as much as possible how everything should work. The guy that came to my house and did this has been in business for over 30 years and I trust them thinking they know what they do.
It is one rod that he installed in the ground that is few feet away from the outside meter/box, the other rod was installed form the electrical company, it was already there, that’s why I thought he did 2.
One of the 20 amp outlet is grounded to the inside of the panel.
The other 20 amp outlet is grounded directly from the outlet to the outside rod with a clamp that is attached to the rod itself, I saw that with my own eyes. It is a straight wire that goes from the outlet to the outside and has nothing to do with the inside panel or anything else in the house.
The other 20 amp outlet is grounded directly from the outlet to the outside rod with a clamp that is attached to the rod itself, I saw that with my own eyes. It is a straight wire that goes from the outlet to the outside and has nothing to do with the inside panel or anything else in the house.
YOU are going to have to find out exactly what the guy did!
Do you feel comfortable pulling the wall duplex outlet from the wall box for a look to see exactly what the guy did?
IF yes. Turn off the breaker at the electrical panel that feeds the outlet. Plug a lamp into the outlet to make sure 100% the power is off. 100%! To verify the lamp is turned on and the bulb is good plug it into a live outlet. Lamp bulb should light.
Pull off the outlet cover plate. Remove the two 6/32 screws that hold the outlet to the wall box. Pull the receptacle outlet straight out from the box far enough to look at the wires that are connected to the receptacle as well as those that enter the box. Is the box metal or plastic? As for the branch circuit wiring that enters the box, I believe you said in an earlier post it is Romex. You should see a black insulated wire (Hot), a white insulated wire (Neutral), and a bare copper wire, the safety equipment grounding conductor.WHERE IS THE BARE WIRE CONNECTED TO???
*****Examples:
1) ** IS THE BARE WIRE connected to the ground wire that comes in from the outside isolated ground rod along with a short wire, pigtail, that connects to the green equipment ground screw on the isolated grounding type receptacle outlet? IF the box is metal the box must also be bonded, connected, to the ground wires connection with another pigtail. All connections should be under one wire connector, example a wire nut. IF this is what you have then the guy wired the grounding per NEC Code as an Auxiliary Grounding Electrode. Lightning loves Auxiliary Grounding Electrodes!
NOT NEC compliant! 2) ** IF a metal wall box was used the Romex cable bare copper safety equipment grounding conductor is bonded, connected, to the metal box ONLY. Period.... IF the box is plastic the Romex Cable bare equipment ground wire is not connected to anything. It is just pushed back inside the box. The ground wire that enters the wall box from the outside isolated ground rod connects to the green color ground screw on the isolated grounding type receptacle ONLY. Period.... If this is the way the guy wired the grounding it is dangerous and could cause an electrical shock hazard or worse possible electrocution in the event of a hot to chassis ground fault event. Also note you do not have a low resistance path for ground fault current to return to the source, the electrical service neutral conductor, in the event of a hot to chassis fault. This would also include anything plugged into the wall outlet. That includes the power cord feeding any equipment. Cut to the case, the breaker in the electrical panel that protects the branch circuit wiring will never trip open in the event of a ground fault event.
//
As for your power quality problem there is always a solution. It may require you hiring a certified credited power quality testing company. In my area they charge around $125 an hour. In your case the tech would be there about an hour or so..... He/she will have the test equipment needed to find your power quality problem. If it is coming in from outside your home the testing company will provide you with the necessary test reports to show to your utility power company. If it is inside your home the power quality company will identify the problem. If it is structure electrical wiring or fixed electrical equipment a licensed electrician will be required to make the repairs. In most cases the power quality company will recommend an electrical contractor company they use. Jim
What
is the difference between the ground wire that is connected to the
panel itself and the one that goes to the outside, it still goes thru
the panel but it is not attached to the panel itself it just goes thru
the pipe that goes outside where the meter is and from there it is
attached to the rod.
All grounds must be bonded together along with the neutral at the service panel. Your separate ground creates a chance that a fault to ground won't trip a breaker. That's the biggest problem with the arrangement and why its an NEC violation.
The
guy that came to my house and did this has been in business for over 30
years and I trust them thinking they know what they do
It's likely that your town requires a permit for this work. Did you check into that?
@OP, I would find another electrician. From what you have described, I would be wary of what the original electrician did-especially with his nasty attitude, and concerned that this setup is according to code. Perhaps the whole problem with the Mac was a blessing in disguise. You might have uncovered a problem that could have become a Big Problem, if a lightning storm struck. Bob
What is the difference between the ground wire that is connected to the panel itself and the one that goes to the outside, it still goes thru the panel but it is not attached to the panel itself it just goes thru the pipe that goes outside where the meter is and from there it is attached to the rod. I am by no means an electrician and I am trying the understand as much as possible how everything should work. The guy that came to my house and did this has been in business for over 30 years and I trust them thinking they know what they do.
What is the difference between the ground wire that is connected to the panel itself and the one that goes to the outside, it still goes thru the panel but it is not attached to the panel itself it just goes thru the pipe that goes outside where the meter is and from there it is attached to the rod.
@ tomiiv30 OP
Like cleeds said that is an NEC violation. It is also not the correct way to connect the IG (Isolated Ground) ground conductor to ground. It can pass through a sub panel to the main panel the sub panel is fed from but it must connect to the ground bar in the electrical panel. Period!
The problem with what you have now the earth is not considered a low resistive path for ground fault current to travel back to the source. In the event of a hot to chassis ground fault the chassis could/would be HOT with respect to any other piece of grounded equipment that is properly grounded within arms length. Heck, you would be better off just using a ground cheater at the outlet to plug the equipment into. At least then you know the outlet is not grounded.
I am by no means an electrician and I am trying the understand as much as possible how everything should work.
The guy that came to my house and did this has been in business for over 30 years and I trust them thinking they know what they do.
If the grounding is wired as you said, the guy is not an electrician either. He just passes himself off as an electrician....... Not all electricians are created equal.
You guys are scaring me big time now, this is Chicago and we got some of the most f’ed up people here that say they are something to later find out that they are nothing. These are guys that have been recommended to me by friends and family. What the heck is this world coming to. And I paid them top dollar and never asked for any discounts or anything, whatever they asked I paid. The last guy that I used the one that has more than 30 years experience, he showed me his license and works for the union and is a foreman.(It could be a big lie). Maybe he is older and stubborn and don’t want to upgrade himself to the newer standards or he is in for the quick money. Just like a mechanic if he tells me to replace the engine I would do it because I trust his word and this is how it should be.
The question now is how do I find an electrician that I can trust?
I don’t believe anyone commenting here is a licensed electrician for your area nor knows your areas electrical codes. I would trust your licensed electrician before any of us. While everyone is trying to be helpful, we are merely speculating at best. If everyone got to you and you are truly worried, have a different licensed electrician come by to look at everything for a second opinion. It will be money well spent for your piece of mind.
Do do you still have the Mac amp or did you take the refund?
I still have the amp, a member of another forum sent me his two Emotiva CMX2 DC blockers and told me to put them in series and after doing so there is still buzz in the amp but quieter than without the dc blockers. Couldn't return it because I was over my returning period. The sales man could do so much, management would not even bother look into my matter, McIntosh is nowhere to be found.
It was an expensive learning experience for me and was a first one for me.
I don’t believe anyone commenting here is a licensed electrician for your area nor knows your areas electrical codes. I would trust your licensed electrician before any of us. While everyone is trying to be helpful, we are merely speculating at best. If everyone got to you and you are truly worried, have a different licensed electrician come by to look at everything for a second opinion. It will be money well spent for your piece of mind.
I will bet you the AHJ in Chicago does not allow the equipment grounding conductor of an IG receptacle to be connected to an isolated earthed ground rod as the OP described the electrician did it.
OP said:
The other 20 amp outlet is grounded directly from the outlet to the outside rod with a clamp that is attached to the rod itself, I saw that with my own eyes. It is a straight wire that goes from the outlet to the outside and has nothing to do with the inside panel or anything else in the house.
OP said:
What is the difference between the ground wire that is connected to the panel itself and the one that goes to the outside, it still goes thru the panel but it is not attached to the panel itself it just goes thru the pipe that goes outside where the meter is and from there it is attached to the rod.
//
2014 NEC® section 250.146 Connecting Receptacle Grounding Terminal to Box
(D) Isolated Ground Receptacles
Where installed for the reduction of electrical noise (electromagnetic interference) on the grounding circuit, a receptacle in which the grounding terminal is purposely insulated from the receptacle mounting means may be permitted. The receptacle grounding terminal shall be connected to an insulated equipment grounding conductor run with the circuit conductors. This equipment grounding conductor shall be permitted to pass through one or more panel boards without a connection to the panel board grounding terminal bar as permitted in 408.40, Exception, so as to terminate within the same building or structure directly at an equipment grounding conductor terminal of the applicable derived system or service. Where installed in accordance with the provisions of this section, this equipment grounding conductor shall also be permitted to pass through boxes, wireways, or other enclosures without being connected to such enclosures
Wording is word for word right out of 2014 NEC, page 70-133.
Nothing said about connecting the equipment grounding conductor to a ground rod. I see no NEC exception given for the OP’s electrician. I also doubt the Chicago AHJ would approve what the guy did either. It’s dangerous! Surely you would agree?
AS for the OP getting another electrician out to house I agree he should. First thing he should do is land the IG equipment grounding conductor on the ground bar in the service electrical panel where it should have been landed in the first place. Then the OP should have the electrician inspect the rest of the work the other guy did.
Chicago? I didn’t think the city of Chicago AHJ allowed NM sheathed cable, (Romex is a manufacturer’s Trade Name for NM), in residential occupancies. My understanding all branch circuit wiring has to be installed in EMT conduit. Did the electrician install Romex? Is your house wired with Romex? Do you actually live within the city limits of Chicago? Jim .
Chicago? I didn’t think the city of Chicago AHJ allowed NM sheathed cable ...
If this guy lives in Chicago, then the work he described would require an electrical construction permit from the city. It would also require that an electrical inspector approve the work before the circuit could be energized. While the permit may cost a few $$$, it would be cheap insurance against the sort of hazardous connections described here.
I am outside of Chicago limits about 20 miles west. I just turned off the breaker for that outlet and would not use it until I find somebody that really knows what he does and to double check if everything is correct or not.
... I just turned off the
breaker for that outlet and would not use it until I find somebody that
really knows what he does and to double check if everything ...
Why don't you get an electrical construction permit? That would probably resolve all of your concerns.
Trying to fix the problem for this amplifier's buzz it made a mess of my house electrical. I shouldn't have done anything but just enjoy my new equipment, now we went totally different direction about fixing something that was not broken in the first place. When I hire someone to do work I expect them to do all the necessary things, if they needed a permit they should've got one, and like I said everything was working just fine before I started adding outlets, even now everything works just fine and maybe everything is correct but I just don't know that what I am saying is correct, maybe I am wording myself wrong. This problem cost me so much time and money and nerves that is giving me nightmares at night.
Amplifier buzz is a thing to fix- but it really shouldn’t have anything to do with the electrical system.
@ atmasphere
It’s not the amplifier that is buzzing loudly. It’s the power toroidal transformer buzzing, vibrating, loudly. It’s a big toroidal transformer capable of delivering 35 amps, continuous. At the vary least the torid would have to be at least rated at 3500Va. And that would really be pushing the torid beyond its’ limit using a 125% SF.
In case you missed the OP post. He took the amp back to dealer. The service dept plugged the amp in, powered it up, and the torid transformer was quiet. No loud buzzing as the OP experiences at his home.
I still have the amp, a member of another forum sent me his two Emotiva CMX2 DC blockers and told me to put them in series and after doing so there is still buzz in the amp but quieter than without the dc blockers.
@ atmasphere
Any thoughts why the blockers didn’t stop the buzzing of the torid? Bad distorted waveform. Harmonics?
Because the toroid isn't manufactured properly; probably not wound properly. More than one example hums because whole batches probably made with sub-par QC. It's all down to the sub-contracted company that M. buys their transformers from these days. Evidently not the same QC, and probably not the same company, as in the old days. Once you stumble over a product that hums regardless of whatever else you do to remedy it, the only thing to do is get rid and move on to a different (and hopefully better) manufacturer. That's what I did. The monoblocks I own now (admittedly not massive) are absolutely silent.
You must have nerves of steel, I would be a basket case. I would have thrown the amp in question through the stores window just out of spite. I would call McIntosh and ask if they could install the DC offset filter inside the amp for a nominal fee. If they balk, tell them you will be calling the states attorney general to file a complaint and also bad mouth them all over social media and in the different online forums. Anything to get their attention. Or, put it up for sale on Audiomart and move on.
If that's the case McIntosh should pick up my bill and make it right for all the troubles I went thru. The salesman from the dealer I bought my amp from told me that they had specialty electrical companies come to the building every so often to make sure everything works properly, and said that they have the best in business when it comes to electrical wiring, installation, construction and whatnot, it is a specialty hifi store and I bet their electrical is top notch. This amp buzzed at three different houses all about 20+ miles apart, and I am still not sold on that it's only me and my electrical. But it is what it is and I have to live with it.
Trying to fix the problem for this amplifier’s buzz it made a mess of my house electrical. I shouldn’t have done anything but just enjoy my new equipment, now we went totally different direction about fixing something that was not broken in the first place. When I hire someone to do work I expect them to do all the necessary things, if they needed a permit they should’ve got one, and like I said everything was working just fine before I started adding outlets, even now everything works just fine and maybe everything is correct but I just don’t know that what I am saying is correct, maybe I am wording myself wrong. This problem cost me so much time and money and nerves that is giving me nightmares at night.
As for correcting the connection of one of the dedicated branch circuit equipment grounding conductor that is now connected to the isolated ground rod, that’s an easy fix. More time will be spent removing the electrical panel cover and replacing it. Connecting the equipment grounding conductor, wire, to the ground bar will take about 1 minute. Removing the ground wire that goes outside to the ground rod 10 minutes, if that.
IF the electrician roughed in steel boxes for the new dedicated wall outlets there is a very good chance they are not grounded. Good chance he just connected the equipment grounding conductor to the ground screw terminal on the IG duplex receptacle outlet. The mounting back strap is not electrically connected to the equipment ground contact on an IG receptacle. Unless the guy connected the equipment grounding conductor to the box, as NEC requires, the box and back strap of the receptacle is not grounded. That would have to be checked and corrected if need be. Time to look at both outlets? 15 minutes. If they need to be grounded? 5 minutes each, if that. Material? Four green grounding pigtails and two wire nuts.
As for the electrician/contractor pulling a permit. I doubt you will find many electricians/contractors across the US that will pull an electrical permit for installing a couple of 20 amp branch circuits. If the customer says he wants the contractor to get an electrical permit then the contractor will do so.
Note the word contractor..... Being a licensed electrician doesn’t mean he/she can pull an electrical permit. He/she is also required to have an electrical contractor license for the city he/she is working in to pull a permit. (In my area an electrical contractor doesn’t have to be a licensed electrician. He/she just has to have a licensed Master A electrician working in a management position. Even if the contractor is an electrician, but not a Master A electrician he/she is still required to employ a Master A electrician working in a management position.
Burning question! Is your house wired with Romex? What did the electrician install for the branch circuit wiring? Jim .
This is what I have for the outlet, now from that orange outlet 3 wires are cumming out and going down to the panel that's in my basement thru the the metal pipes which I think are called "conduit". Wires are Black, White and Green. All 3 wires are in the panel, black is connected to the breaker, white is screwed to the panel it self on the right side and the green one goes outside to the copper rod. Now I talked to another electrician just now and he said to me that the way green wire is done it is probably not up do code but he said that even they it is should not be a problem. He said he can come to the house and have the green wire installed inside on the panel but before he does that he said he will install some kind of a self isolated part on the panel and that green wire would attach to it. Than he said from that part he will install conduit to the water meter where he will have a grounding wire from that part to the water meter. ( That's how I understood him)
Per the NEC the EMT conduit is considered an equipment grounding conductor, Not sure if Chicago AHJ does though. I would imagine they do. Therefore per NEC the steel outlet box and supporting back strap of the IG duplex receptacle is grounded.
Now I talked to another electrician just now and he said to me that the way green wire is done it is probably not up to code but he said that even they (then) it is should not be a problem.
Man, that was an eye opening video. Now let me tell you something, I was told to do the copper rod by many of this or other forums to do what I have done and think that is the right way and that it should work.
After watching the video it explained very well how everything should be done and I don’t think lot of electricians know this let alone audiophiles that thin they know but they know nothing. He also mentioned us the audio guys are doing extra rods to get isolated grounding.
McIntosh winds all their transformers in house. Don't let anyone tell you different. I toured the factory and watched the person doing it. This person has been doing it for over 40 years at McIntosh.
Yeah but that doesn't mean that they don't use somebody else to do the transformers for the less expensive amps like mine. There is another one or two threads on Audiokarma with the same problem as mine. I mean this lady is getting old and is the only one at the factory as far as I know and how much more can she do - right?
Wow, what a clam bake this turned into... @tomiiv, If your dealer's wiring doesn't produce hum in your amps, I don't see why he didn't have his 'electricians' check your wiring. But, considering how you have been treated, I would be circumspect about asking them to look at your wiring. There must be a listing of Master Electricians locally. And, one who has experience in home stereo wiring. Bob
@tomiiv30............ There are two people that wind transformers at McIntosh. That fact that the amp doesn’t buzz at the dealer is proof the transformer isn’t defective. Weather or not there is noise on your line I am unable to debate. There is not a part of the McIntosh factory that works on the “cheaper” equipment. I can say this because I have toured the factory twice. I do think McIntosh should do the right thing and give you all your money back. They won’t be losing anything other than a quick refurbishing and it would reinstore your faith in the company. Shame on them for not living up to their reputation in satisfying every customer.
Toroidal transformers has no airgap like old E I laminations or c-cores which means they have a very small stray field. A gap will minimize the DC saturation, so yes DC is bad but how much before the toroid starts humming from saturation. As the transformer is very heavy it is possible it may have shifted in transit. Is it epoxy potted or mounted on a rubber disc? Make sure nothing is connected to the center bolt as this could make a secondary turn on the toroid, inducing a load or a voltage. Been there...
This experience is saddening. I have direct experience in Residential Electrical as well as solid state electrical design and build. Do not buy extraneous equipment to solve this issue if you live in a house. I know the Mac is heavy but are you able to take it to a friends house and reproduce the humming? If yes, the Mac is bad and keep returning until good or a different model if stuck on Mac (oh no!). This isolated circuit does nothing for 'this' issue and is a waste because you're sharing a neutral eventually at the panel...the intermediate copper ground poles is a scary idea and grounding does not solve equipment or wiring defects. It is for personal and equipment safety that we 'ground'. A neutral is already a grounded conductor as its called and all that is bonded with the code required double ground requirements (like the buried copper rods) at the panel as well.
I think you have a bad/shared neutral somewhere in your house (or severely unbalanced neutral). Though fairly new, it doesn't determine the exactness of the junior electricians doing the house wiring. It only takes one miswiring or modification to cause this,especially with 240V coming to your panel, which is then split into separate 120V sharing the same neutral at the panel, or branch circuits with a shared neutral that shouldn't be shared. The Mac should not be affected by this however and thus it is bad. The very nature of what it does with the incoming AC should have filtered this out. I'm surprised the electrician can't identify the source. Otherwise, very remotely, its a bad neighbor introducing issues from poorly implemented solar grid tie, etc. (you share power lines) but the 'electric company' can verify that as a last resort (that you have zero DC offset at the panel...where their responsibility ends).
I have never seen 'buzz' from good equipment...but there's alot I haven't seen as well.
This guy has a warrantee he should just return the component to the manufacturer for repair and while it is there hire a trained, competent, licensed electrician to correct the improper, faulty, and dangerous connections previously constructed by the prior contractor also he should name hear the dealer that sold him this component why hasn't he already mentioned that?
All the emphasis is on McIntosh's famous output transformers. Little mention of the IE power transformer. Search Audiogon for McIntosh + hum. There are threads going back years.
No need to name names for the dealer, they have done so much actually they have done as much as they knew because they have not been trained by McIntosh to deal with this kind of situations. They did not know about this problem until I brought it up to them, and even them can’t get any clear answers back from McIntosh as to how this should be dealt with. All McIntosh did was to tell me and my dealer that I have DC on my mains and how they know if I have Dc offset I have no idea they never came to my house to check, and that was that no more interactions. It looks like I am on my own. They replaced two units so far one being the one discussed in this thread and another one that had loose parts.
If you did not read my previous posts, this unit that buzzes like crazy at my house and at two different houses, did not buzz at the dealer at all and it was dead quite - How is that possible I have no idea and I think that even if I return this unit back to the manufacturer they would say the same thing that this unit works properly. Also the warranty time that it would take to send and receive the unit back it would be about a year or maybe 6 moths the least.
And round and round we go. It's this, it's that, believe me. You made a simple case for me anyway. You took the unit to 3 different houses miles apart from each other with the same humming result. What more has to said? Defective unit, no?
4krow "What more has to said? Defective unit, no" If the claim that it was defective was valid, authentic, and genuine then why wouldn’t this person who came hear only to complain return the unit to McIntosh for repair, adjustment, or replacement and why wouldn’t he name the dealer who sold him this defective, damaged, or inferior unit?
I hope Tom bought it from a very good dealer with a lot of cash flow. Some stores would be unable to refund that amount of money as many rob Peter to pay Paul. I hope for a happy ending.
The dealer in my area has a no return policy. You buy it, you own it. And they are not small by any means. They probably have a million dollars of audition demo equipment and speakers in various rooms in the store. They probably sell more ARC equipment in the Midwest than anyone else. And yes they sell McIntosh.
I asked the dealer, several years ago, why he didn’t have a return policy like the other dealer in our area. They offer a 7 day return policy. The dealer responded with another question to me. "What does he do with a returned piece of sold equipment?" "Repackage it and resale it for new?" "Put it on the floor and sell it as a demo?" Once it was sold and taken home by a customer it became used. And then he said something like, used is used. .
And round and round we go. It’s this, it’s that, believe me. You made a simple case for me anyway. You took the unit to 3 different houses miles apart from each other with the same humming result. What more has to said? Defective unit, no?
He took the amp to 2 other houses, not 3, and it buzzed. Was it as loud as it was in his home? I don’t remember if the OP said. He took the amp to the dealer where he bought it. It was put on a bench in the service department, plugged in, turned on, and no buzz. The OP said it was quiet. Defective equipment? No. McIntosh was just too tight to incorporated a DC blocker in the unit. Like I said in an earlier post I bet the design engineer designed it using a DC blocker. .
So I took the amp to 2 of my friends houses and I meant 3 total including my house. Why this unit has no been returned is that when I took it to the dealer it was dead quite, so if I was to send it back to McIntosh I would get the same answer back as the dealers, that the unit is not defective and by all means this unit is not defective it plays music and movies very well except that the buzz is so loud you can hear it in the other room. I am not complaining about a defective unit, I am complaining that McIntosh should've invented something to put in this kind of amplifiers so when we get them we don't hear this buzz.
And as far as naming the dealer, even if I told you who sold it to me, what difference would that make. They are just a dealer and a re-seller of a high end equipment. I think IMHO that it is up to the manufacturer to make sure this units work properly everywhere in every single household no matter what electricity, since we all cannot have perfect electricity right?
I mean this dealer just started selling McIntosh like not even a year ago and they did try to resolve this problem by getting me a second new unit that did the same thing, the thing is maybe the units are working as they should it just that they have this buzz that many of us get, that's all. Some are bothered by it (like me), some aren't. And IMO when spending this kind of money we should not deal with this kind of problems.
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