How to tame a really noisy AC circuit. Transformer? Line Selective UPS?

Kingrex

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Feb 4, 2019
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Here is a fun trick with your Entec. Pull the receptacle out of the box as far as it will pull out with the wires attached. Put the Entec as far into the box as possible, then draw it out towards the receptacle. Take the sniffer right up to the screw clamps. My guess is the screw terminals are by far the noisiest point along that line.

You may want to turn off the power, pull rhe duplex out, tape the duplex screws so you don't get shocked, then turn it on for the test

While the powet is off, test the receptacle with the sniffer. Then test it with the power on.

With the Entec stuffed into the box against the wire, start unplugging all devices plugged into the branch wire shared with your audio circuit. Does the noise drop.
 

Kingrex

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A possible solution to your noisy circuit would be to explore establishing a separate circuit for your listening room and then installing a separate external ground rod. You circuit sounds like it is very noise and it may be because of what you have on it. You may want to explore that. It also sounds like you need to isolate your circuit/system from other sources of noise and having a separate circuit and ground for your system could, as it did for me, make a VERY noticeable improvement to the whole system at a somewhat modest cost -i.e. a copper 8' ground rod is approximately $20.00 with the hook up hardware and wiring adding perhaps another $20.00 and a separate circuit breaker adding another $25.00 to the overall material cost. If you do what I did you can have the ground rod installed through your basement wall which has the advantage that there is nothing above ground outside to corrode and otherwise deteriorate. If you do this the patch material for the hole in your basement wall is perhaps another $6.00 - the hole should not be more that 3/4" round. You will need/should have an electrician do all of this which is likely to cost you perhaps an additional $225.00 labor. Bottom line cost is likely not to exceed $325.00 and it is by far one of the single best improvements I have ever done for my system. Good luck.
I hope you are merely advocating adding an additional ground rod to the main panel. That can provide great sonic gains.

If however you are advocating to take the branch circuit ground from the duplex direct to the rod, that is illegal and dangerous. I would ask you never post on forms reckless advise that can kill people and damage equipment.

Thanks
 

bazelio

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I hope you are merely advocating adding an additional ground rod to the main panel. That can provide great sonic gains.

If however you are advocating to take the branch circuit ground from the duplex direct to the rod, that is illegal and dangerous. I would ask you never post on forms reckless advise that can kill people and damage equipment.

Thanks
Kingrex, how can a separate ground rod for a sub panel kill people? Serious question.
 

Kingrex

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Incorrect Ground Jensen.jpg
 

Kingrex

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If a fault in your tube amp goes to ground (the case of the amp) then 900 volts would go out the ground wire to the ground rod. The rod does not have enough resistance in the earth to get back into the panel to trip the breaker. So you now have 900 volts at probably 16 amps or so injected into the earth radiating out from the ground rod. Anyone who is standing on the ground that touches something grounded such as a hose bib, cable TV isolator, power mast, metal siding. That person will get hundreds of volts.

The other issue is lightening. If it strikes the ground anywhere near the double rods, it will go up both rods at different potential looking to find the utility. They use to ground industrial equipment like this until they realized every lighting storm was burning out the solid state components in their power supplies and controllers. It creates a massive EMF pulse in any devices between the 2 rods.

Also, if your new ground is anywhere near the old ground, you can create a ground loop in the earth. It is easy to measure hundreds of millivolts of potential between 2 rods driven in this way.

If you believe you are hearing sonic gains by grounding incorrectly, then I am going to say, you don't have your main panel grounded proper. Your main panels is probably grounded legally and NEC compliant. But its not optimized for audio. Just like a piece of audio equipment, there are some pieces that are built very well and you can hear it. There are others that are slapped together and work fine for the masses. But you would not want it in your high end audio listening environment.
 
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pmiller

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Oct 8, 2020
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I hope you are merely advocating adding an additional ground rod to the main panel. That can provide great sonic gains.

If however you are advocating to take the branch circuit ground from the duplex direct to the rod, that is illegal and dangerous. I would ask you never post on forms reckless advise that can kill people and damage equipment.

Thanks
I would suggest re-reading my proposal. I thought my reference to a separate circuit, a separate ground rod along with soliciting the services of an electrician was clear but apparently for some it wasn't. My goal was to try to make a useful suggestion that has worked for me and your counsel that I should not post something than can kill people wasn't necessary since my posted suggestion wasn't dangerous in the first place.
 

Kingrex

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Feb 4, 2019
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I would suggest re-reading my proposal. I thought my reference to a separate circuit, a separate ground rod along with soliciting the services of an electrician was clear but apparently for some it wasn't. My goal was to try to make a useful suggestion that has worked for me and your counsel that I should not post something than can kill people wasn't necessary since my posted suggestion wasn't dangerous in the first place.
Your post was vague. See post #44. That is what I thought I was reading.

I did note if your just adding a rod to the main panel that is great. I have no justification as to why, but I believe I have heard sonic improvements by adding a good set of rods to a service that for all intent and purpose has a good cold water ground.

FWIW, a shocking numbet of electrician don't know why post #44 is dangerous. They just role along doing what the customer asks for. I have taken numerous grounding courses. I have spent countless hours studying grounding. Its more complex than one might think.
 

bazelio

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If a fault in your tube amp goes to ground (the case of the amp) then 900 volts would go out the ground wire to the ground rod. The rod does not have enough resistance in the earth to get back into the panel to trip the breaker. So you now have 900 volts at probably 16 amps or so injected into the earth radiating out from the ground rod. Anyone who is standing on the ground that touches something grounded such as a hose bib, cable TV isolator, power mast, metal siding. That person will get hundreds of volts.

The other issue is lightening. If it strikes the ground anywhere near the double rods, it will go up both rods at different potential looking to find the utility. They use to ground industrial equipment like this until they realized every lighting storm was burning out the solid state components in their power supplies and controllers. It creates a massive EMF pulse in any devices between the 2 rods.

Also, if your new ground is anywhere near the old ground, you can create a ground loop in the earth. It is easy to measure hundreds of millivolts of potential between 2 rods driven in this way.

If you believe you are hearing sonic gains by grounding incorrectly, then I am going to say, you don't have your main panel grounded proper. Your main panels is probably grounded legally and NEC compliant. But its not optimized for audio. Just like a piece of audio equipment, there are some pieces that are built very well and you can hear it. There are others that are slapped together and work fine for the masses. But you would not want it in your high end audio listening environment.

Right so the remote panel's grounding system floats at 120V after a fault, and that's dangerous. I put a 240V subpanel in my garage, and ran 4 wires. At the time I installed it, the local code said that since it's within the same building, I didn't need a second ground rod, just the ground wire. To install a second ground rod, I'd need to drill through the concrete in my garage floor, and I don't even know how thick it is. But this is the panel that feeds my audio system. Normally, everything else on the panel is switched off, so in effect, the subpanel is dedicated to my audio. Do you think I would realize a benefit from going through the hassle of adding a second ground rod at the subpanel?
 

jerrybj

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Feb 28, 2022
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I have a massive hum coming from my integrated amp.
Sent it to be recapped late last year, and the technician said "What hum?"

Have added an Audiolab DC Block which has reduced it slightly.
What other options do I have?
Mains power is 230V.
 

Alrainbow

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Does the amp hum to speakers with input shunted ?
Same as above but no input connections ?
what voltage is the amp ?
start here please
 

jerrybj

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No hum through the speakers.

Hums with no connections.
Amp is 200w Perreaux R200i.
Mains power is 230v, as is amp.
The R200i is a dual-mono design, with two large toroidal transformers.
 

Alrainbow

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So what your saying is
it’s an audible acoustic hum from the amp
?
if yes does the hum vary ? Lees or more at certain times ?
 

GroovySauce

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Nov 9, 2020
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I have a Greenwave EMI meter. Construction looks identical to the Trifield, different branding.

I bought 6 or 8 of the Greenwave EMI filters. They reduced the readings from 250+mV to around 20mV, depends on time of day.

I have a Torus AVR 15 the older model. I have a component that makes the reading on the Torus read ~1,500mV. On the wall side it will read ~40mV.

Plugging one of the Greenwave filters into the back of the torus will reduce it to ~150mV. This is where it gets interesting. It is a negative effect on the music. It sucks some of the life out of it.

On the flip side, lowering the room circuit noise benefited the music. This was before the Torus was in the system, so that may not be true anymore.

My system shares the same breaker as other outlets in the room.

There are other companies that make similar products to Greenwave. For $250, I’m happy with the purchase. I bought it for the claimed health benefits. I notice I sleep better after installing them. That could be confirmation bias. I'll take it either way.
 
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bazelio

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I have a Greenwave EMI meter. Construction looks identical to the Trifield, different branding.

I bought 6 or 8 of the Greenwave EMI filters. They reduced the readings from 250+mV to around 20mV, depends on time of day.

I have a Torus AVR 15 the older model. I have a component that makes the reading on the Torus read ~1,500mV. On the wall side it will read ~40mV.

Plugging one of the Greenwave filters into the back of the torus will reduce it to ~150mV. This is where it gets interesting. It is a negative effect on the music. It sucks some of the life out of it.

On the flip side, lowering the room circuit noise benefited the music. This was before the Torus was in the system, so that may not be true anymore.

My system shares the same breaker as other outlets in the room.

There are other companies that make similar products to Greenwave. For $250, I’m happy with the purchase. I bought it for the claimed health benefits. I notice I sleep better after installing them. That could be confirmation bias. I'll take it either way.
When you plug in the Greenwave and you say it sucks some of the life out (a common problem with audiophile power products also), is it just dangling or do you plug any component into the Greenwave?
 

GroovySauce

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Nov 9, 2020
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When you plug in the Greenwave and you say it sucks some of the life out (a common problem with audiophile power products also), is it just dangling or do you plug any component into the Greenwave?
Nothing is plugged into the Greenwave. It only sucks the life out when it's in the back of the Torus. Nothing plugged into the Greenwave still. When they're plugged in to other outlets in the circuit there is an improvement. Very small improvement.

My first reason for putting the Greenwave filters in was to lower total house EMF pollution. The system change was an added benefit.
 

bazelio

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When plugged in to the other outlets in the circuit, do you see a measurable noise reduction out of the Torus?
 
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Atmasphere

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I would suggest re-reading my proposal. I thought my reference to a separate circuit, a separate ground rod along with soliciting the services of an electrician was clear but apparently for some it wasn't.
Even re-reading this post, its still not clear that the ground post is actually for the main panel ground. This post makes it sound (to me anyway) like the ground post is somewhere else in the circuit (re.: 'a separate circuit, a separate ground rod').
 

Folsom

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If you have a ground rod that isn't tied to neutral in the breaker box then the path to drain it is much higher resistance. If it can instead choose another path back to neutral (that could involve you) it can be very dangerous.

You have to get a short to ground for that to happen. Over current does not specifically have to involve ground. Both will trip the breaker but the power must drain. The bond between neutral and ground in the breaker box is the lowest resistance path, not the ground rod. The ground rod is mostly for lightening. It's a huge noise source but gives a path to drain.

The OP might just be picking up RF that'll disappear when using equipment because right now it might be a longer run that's more tuned to certain RF, dangling out on it's own. I'd agree it isn't a problem yet. However one might want to consider a dedicated line because some share grounds and power that really do cause issues. Lights that dim are one of the worst ever - and are commonly very audible.

When it comes to a conditioner or such I'm not sure of any very cheap solutions to anything. There are things, but they suck for the most part. And when I suck, I mean you can hear it sound bad. Oh wait even most expensive solutions are terrible.

1. Listen to stereo.
2. Dedicated line if yours currently shares.
 
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