@twoleftears
Do they really buy their transformers from somebody else and are not wound in-house?
Do they really buy their transformers from somebody else and are not wound in-house?
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
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
- ...
- 225 posts total
tomiiv30 OP37 posts01-22-2019 10:25am 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 . |
@jea48 https://www.homedepot.com/p/Leviton-20-Amp-Industrial-Grade-Heavy-Duty-Isolated-Ground-Duplex-Outlet... 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) |
@ tomiiv30 OP Your branch circuit wiring is more than likely installed in EMT (Electrical Metallic Tubing). https://www.homedepot.com/p/1-2-in-x-10-ft-Electric-Metallic-Tube-EMT-Conduit-853428/100400405 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. Stop! Find another electrician! Keep looking. This guy sits on one of the NEC (National Electrical Code) boards that helps write electrical safety code. Watch the video. https://www.youtube.com/watch?time_continue=2&v=qNZC782SzAQ Now what did the electrician tell you over the phone again? I know Chicago has good electricians. Jim . |
@jea48 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. |
- 225 posts total